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'Homecoming' Reached 1.1M US Viewers in Its First Day
Netflix's critically-acclaimed concert special Homecoming: A Film By Beyoncé reached 1.1 million U.S. viewers on its April 17 premiere date, according to data newly provided by Nielsen via its SVOD Content Ratings system.
Introduced in October 2017, SVOD Content Ratings measures the viewership of subscription video on demand (SVOD) services via audio recognition software installed in 44,000 U.S. homes that contain Nielsen's TV set meters. While the highly-secretive Netflix has stated in the past that Nielsen's ratings are "not even close" to being accurate, it is the most reliable measure yet of SVOD viewership data.
According to the numbers compiled by Nielsen, the audience for Homecoming was 63% African American on the day of its premiere and 55% over its first seven days, more than any other Netflix original film or series analyzed to date (the closest was Bird Box with 24%). Hispanics, meanwhile, made up 15% of viewers, while Asians comprised 5%.
'Before I Let Go' Becomes Beyonce's 60th Hit on Billboard Hot 100
Beyoncé makes her 60th appearance on the Billboard Hot 100 chart as "Before I Let Go (Homecoming Live)" debuts at No. 75 (on the list dated May 4). The single, released April 17 as a bonus track on her Homecoming: The Live Album, bows after its first full week of tracking.
The cover of the 1981 hit by Maze featuring Frankie Beverly, which reached No. 13 on the Hot Soul Singles chart (now Hot R&B/Hip-Hop Songs) enters with 6.9 million U.S. streams in the week ending April 25, according to Nielsen Music. It also starts at No. 28 on Digital Song Sales with 6,000 downloads purchased in the same window.
Though "Go" doesn't yet make the all-genre Radio Songs chart, the single has claimed a fast start at R&B/hip-hop radio, bursting 45-27 on R&B/Hip-Hop Airplay with 7.2 million in audience in the week ending April 28.
In addition to its Hot 100 start, "Go" also opens at No. 45 on Hot R&B/Hip-Hop Songs (which, like the Hot 100, blends streaming, sales and airplay data). Homecoming, meanwhile, ascends 7-4 on the all-genre Billboard 200 and 4-2 on the Top R&B/Hip-Hop Albums charts following its first full tracking week.
'Lemonade' Returns to Top 10 on Billboard 200
It's a big week for Beyoncé on the Billboard 200 albums chart, as the diva claims a pair of concurrent top 10 albums for the first time.
Her 2016 album Lemonade re-enters the list at No. 9 following its wide streaming release, and Homecoming: The Live Album jumps 7-4 after its first full chart tracking week of activity. Further, two more Beyoncé albums dot the list, as both I Am… Sasha Fierce and her self-titled set re-enter the tally.
The Billboard 200 chart ranks the most popular albums of the week in the U.S. based on multi-metric consumption as measured in equivalent album units. Units are comprised of traditional album sales, track equivalent albums (TEA) and streaming equivalent albums (SEA). The new May 4-dated chart, where Lemonade re-enters at No. 9, will be posted in full on Billboard's websites on April 30.
Homecoming: The Live Album rises 7-4 after its first full chart tracking week of activity, earning 57,000 equivalent album units (up 47%) in the week ending April 25. The album gains in both SEA and TEA units, but declines in album sales (8,000; down 43%). On the April 26-dated chart (reflecting the tracking week ending April 18), the album debuted on the list from just two days of activity, as it was released on April 17.
Beyonce's 'Homecoming' Album Debuts in Top 10 on Billboard 200
Beyoncé's surprise-released Homecoming: The Live Album debuts at No. 7 on the Billboard 200 chart with 38,000 units earned from just two days of tracking activity (with 14,000 of that sum in album sales). The album dropped with no warning in the very early hours of Wednesday, April 17, and the tracking week for the chart ended on April 18. (Billboard's album charts' tracking week runs Friday through Thursday.)
Homecoming: The Live Album was released to digital retail and streaming services shortly after the premiere of Beyoncé's Homecoming film on Netflix at 12:01 a.m. on April 17. Both projects chronicle Beyoncé's headlining performances at the 2018 Coachella Valley Music and Arts Festival.
Homecoming: The Live Album is Beyoncé's eighth top 10 album as a soloist. She also recently visited the top 10 as one-half of The Carters (alongside husband Jay-Z) with 2018's No. 2-peaking Everything Is Love.
It's possible that Homecoming: The Live Album could rise higher on next week's Billboard 200 chart (dated May 4), after its first full tracking week of activity.
On the Run II Tour Finishes with More Than $250 Million
They say it's a marathon, not a sprint. But for Beyoncé and JAY-Z, it was both. Their sprawling On the Run II Tour finished with $253.5 million in the bank, according to figures reported to Billboard Boxscore.
The trek wrapped Oct. 4 at Seattle's CenturyLink Field, the last of the 48 stadium dates they played, after beginning June 6 at the Principality Stadium in Cardiff, Wales. From there, the dynamic duo played 18 shows throughout Europe, peaking at London Stadium's two-night engagement with $11 million grossed and more than 125,000 tickets sold. After a few final shows in France, including their debut performance of "APESHIT" in Paris, they crossed the pond for 30 North American shows, with doubles in Landover, Md.; East Rutherford, N.J.; Chicago; Atlanta; Houston; and Pasadena, Calif. The biggest earner of the tour was the Aug. 25-26 engagement at Atlanta's Mercedes-Benz Stadium, grossing $14.1 million.
On the Run II is the sequel to 2014's On the Run Tour, a massive success in its own right. Billboard named it the Top R&B/Hip-Hop tour of the year, coming in at No. 8 on 2014's overall Top Tours list, with three appearances on the year-end Top Boxscores ranking. The original trek grossed $109.6 million from 980,000 tickets sold.
But despite the high bar set four years ago, On the Run II expanded The Carters' worldwide reach. The $253.5 million haul of this year's run represents a 132 percent increase over the original's gross. While one might worry that expanding from 21 sold-out stadium dates to 48 would be spreading oneself thin, Beyoncé and JAY-Z were still able to increase their average per-show gross, maintaining a pace of $5.28 million each night.
Beyoncé & JAY-Z's On the Run II Tour Surpasses $150 Million Earned
Beyoncé and JAY-Z's On the Run II Tour tops the Hot Tours list dated Aug. 25, thanks to the latest batch of earnings reported to Billboard Boxscore for the couple's successful trek. Their placement is fueled by recent engagements in Minneapolis, Detroit, and two sold-out shows for 86,000 fans at Chicago's Soldier Field, which totaled $21.2 million in grosses.
With the addition of these four dates, Beyoncé and JAY-Z's co-headline trek exceeds $150 million grossed, rising to a total of $150.7 million. Across 29 shows in Europe and the U.S., total attendance has reached 1.4 million. There are 19 dates left to report to Boxscore before the tour closes on Oct. 4 at Seattle's CenturyLink Field.
With another month and a half of dates still ahead for Beyoncé and JAY-Z, their tour is trending toward the $250 million mark. As implied by the tour's name, it is the sequel to their original 2014 On the Run stint. The 2018 installment has already blown past its predecessor, which brought in $109.6 million.
The couple's massive summer tour caps off a particularly fertile few years of their storied careers. They released a pair of complimentary albums, Beyoncé's Lemonade in 2016 and JAY-Z's 4:44 the following year. Combined, these two efforts yielded 21 entries on the Hot 100 and earned 3.5 million equivalent album units according to Nielsen Music. Together, they completed the trilogy with 2018's Everything is Love, billed to The Carters. The joint album, released in the middle of their European leg, topped five Billboard charts dated June 30, 2018, including Top R&B/Hip Hop Albums, Top Rap Albums, and Digital Albums.
On The Run II Tour European Leg Grosses $87.6M
With the combined star power of Beyoncé and Jay-Z, it comes as no surprise that the first leg of the couple's "OTR II Tour" was a wild success. Pollstar's Boxoffice has received reports for the entire 18-night European excursion – and every single show sold out.
Presented by Live Nation Global Touring in association with Beyoncé's Parkwood Entertainment and Jay-Z's Roc Nation, the stadium outing kicked off June 6 at Principality Stadium in Cardiff, Wales. That gig sold 39,731 tickets and grossed nearly $4.2 million (£3.1 million).
The European run racked up a total of 871,012 tickets sold and grossed more than $87.6 million. The average show sold 58,067 tickets and grossed more than $5.8 million, with tickets ranging in price from as low as €10 ($11.69) in Rome and Milan, Italy, to as high as €175 ($204.44) in Barcelona. The average ticket price was $100.57, which would seem a bargain to catch two of the biggest artists around.
The biggest stop of the European leg was the two-night stand at London Stadium, which sold a total of 126,443 tickets and grossed nearly $11.2 million. The London show also happened to be the location for the couple announcing the surprise release of their collaborative Everything Is Love album. The other cities that were treated to two nights of The Carters were Paris and Amsterdam.
5 Songs From 'Everything Is Love' Debut on Billboard Hot 100
As Beyoncé and JAY-Z earn their first charted album as a duo, as Everything Is Love, billed as by The Carters, opens at No. 2 on the Billboard 200 with 123,000 equivalent album units, according to Nielsen Music, five tracks from the set debut on the Billboard Hot 100.
"Apes**t" debuts the highest of the bunch on the Hot 100, at No. 13. Sparked by its official video, the song arrives with 24.1 million U.S. streams in the tracking week, as well as 20,000 downloads sold.
The Carters' "Boss" debuts at No. 77 on the Hot 100, followed by "Summer" at No. 84, "Nice" at No. 95 and "Friends" at No. 99.
Beyoncé and JAY-Z have each tallied 59 and 97 solo entries on the Hot 100, respectively. The husband-and-wife luminaries have logged eight shared Hot 100 entries under their usual monikers (Beyoncé and JAY-Z), including the eight-week No. 1 "Crazy in Love" (credited to Beyoncé featuring JAY-Z) in 2003.
Everything Is Love concurrently debuts at No. 1 on the Top R&B/Hip-Hop Albums chart, while "Apes**t" opens at No. 9 on Hot R&B/Hip-Hop Songs.
Beyonce Albums Re-Enter Billboard 200 Chart After Coachella
Beyoncé's debut at the Coachella Valley Music and Arts Festival on April 14 powered big gains for her music sales and streams in the U.S. in the week ending April 19, according to Nielsen Music.
The diva headlined the second night of the festival, which was streamed live on YouTube. Her well-received performance featured her husband JAY-Z, her sister Solange and a Destiny's Child reunion alongside group members Kelly Rowland and Michelle Williams .
Combined, the album and song catalog of both Beyoncé and Destiny's Child saw an 83 percent increase in sales in the week ending April 19, as the two acts combined sold 8,000 albums (up 102 percent from 4,000 a week earlier) and 37,000 digital tracks (up 79 percent from 21,000).
The biggest-selling album between the two acts was Beyoncé's 2016 set Lemonade, which re-enters the April 28-dated Top Album Sales chart at No. 24 with 5,000 sold (up 142 percent) -- its best sales frame since the week ending Dec. 28, 2017.
On the Billboard 200 -- which ranks the most popular albums of the week in the U.S. based on multi-metric consumption -- Lemonade re-enters at No. 91, while her self-titled 2013 album returns at No. 138 and 2008's I Am… Sasha Fierce jumps back onto the tally at No. 160.
Beyoncé & Destiny's Child Sales Soar After Coachella
Not only did Beyoncé's Coachella 2018 performance make history and shake pop culture, it also sold a ton of music. In particular, that snazzy Destiny's Child reunion where Kelly Rowland and Michelle Williams harmonized with Bey to sing "Soldier," "Lose My Breath" and "Say My Name," ushered in a major bump in digital sales.
According to Nielsen, after the performance ended, digital song sales for Destiny's Child hits soared some 767% on Sunday, April 15, not even 24 hours after the group collectively wowed the crowd. The trio is marking the 20th anniversary of the chart-topping girl's group, and the sudden uptick in downloads means the ladies have not lost relevancy even though they don't often perform live together. As for Bey, though it's hard to fathom that there are some people out there who don't already own her music, she still managed to sell yet more of it. Digital song sales for Beyoncé's catalog saw a 228% increase compared to a baseline established prior to Coachella.
Beyonce, with 7,000 units sold, overall moved more units because her baseline is larger than that of Destiny's Child, which moved around 1,200 units, according to Nielsen.
Of all that music, the song "Hold Up" was the top-selling track for Beyoncé with a sales spike of 287%.
The singer's most recent album, Lemonade, hit the number 1 spot on the overall worldwide iTunes chart, as well as national charts in Brazil, Denmark and Norway. In the United States, it ascended to the fifth position.
Beyonce's Coachella Performance Broke YouTube Viewing Record
As arguably one of the best live shows of recent times, Beyoncé's Coachella performance broke a major viewing record on YouTube during its live stream on Saturday, April 14. According to a press release, this year's Coachella was reportedly the festival's biggest to date, bringing over 41 million live views from fans in 232 countries over the weekend. Beyoncé's Saturday stage show alone garnered 458K simultaneous viewers around the world, making her awe-inspiring presentation the most viewed Coachella performance of all time, as well as the most viewed live music festival ever on YouTube.
Amidst the performance, Beyoncé became the first black woman to ever headline Coachella in its nearly 20-year history, and she absolutely made it a point to use the platform to showcase all of the beauty of her roots throughout the entire history-making night. Making mention of the monumental moment, Beyoncé spoke to the audience, saying, "Thank you Coachella for allowing me to be the first black woman to headline."
'Perfect' No. 1 on Hot 100 for 5th Week
Ed Sheeran and Beyoncé's "Perfect" tops the Billboard Hot 100 for a fifth week. The song also takes over as the most-heard hit on U.S. radio, reaching No. 1 on the Radio Songs chart.
"Perfect," released on Atlantic Records -- first as a solo track by Sheeran on his album ÷ (Divide) -- spends a sixth week at No. 1 on the Digital Song Sales chart with 109,000 downloads sold (down 34 percent) in the week ending Jan. 4, according to Nielsen Music.
The song also lifts 2-1 on the Radio Songs tally, up 7 percent to 139 million audience impressions in the week ending Jan. 7 (with radio playing both Sheeran's original solo version and the duet). Sheeran scores his second Radio Songs leader, following ÷ lead single "Shape of You," which reigned for 12 weeks beginning last Feb. 25.
Beyoncé adds her sixth solo Radio Songs No. 1 and first in nearly nine years. Her previous toppers: "Crazy in Love," featuring JAY-Z (eight weeks, 2003); "Baby Boy," featuring Sean Paul (nine, 2003); "Check on It," featuring Slim Thug (three, 2006); "Irreplaceable" (11, 2006-97); and "Single Ladies (Put a Ring on It)" (five, 2009). Beyoncé first ruled Radio Songs as a member of Destiny's Child with four singles (consecutively) in 2000-01: "Say My Name," "Jumpin', Jumpin'," "Independent Women Part 1" and "Survivor."
On Streaming Songs, which "Perfect" led for a week, the song slips 2-4 with 36.4 million U.S. streams (down 4 percent) in the week ending Jan. 4.
Ed Sheeran & Beyonce's "Perfect" Spends 4th Week At #1
It's a New Year, but Ed Sheeran's "Perfect (duet with Beyonce)" is still the hottest song in America.
The smash tops a fourth consecutive edition of the Billboard Hot 100 chart.
The ballad managed the feat by accruing the following in the US this tracking week: 163,000 digital downloads, 37 million streams, and a radio audience of 129.6 million.
Can this power pair make it a 5th week at #1? Stay tuned!
'Perfect' Tops Billboard Hot 100 for Third Week
Ed Sheeran and Beyoncé's "Perfect" rules the Billboard Hot 100 for a third week, remaining the top-selling song of the week and ranking as the most-streamed title for the first time.
Sheeran and Beyoncé's "Perfect," released through Atlantic Records, and first as a solo song by Sheeran on his album ÷ (Divide), spends a fourth week at No. 1 on the Digital Song Sales chart, up 55 percent to 151,000 downloads sold in the week ending Dec. 21, according to Nielsen Music, good for the Hot 100's top sales gain. Aiding its momentum: its new "Perfect Symphony" version with Andrea Bocelli (which accounts for 32 percent of the song's total sales for the week).
"Perfect" also takes over atop the Streaming Songs chart, gaining by 9 percent to 43.4 million U.S. streams in the week ending Dec. 21. Sheeran scores his second Streaming Songs No. 1, following "Shape of You" (four weeks on top beginning March 25), as does Beyoncé, whose "Drunk in Love," featuring JAY-Z, led for four weeks in 2014.
On Radio Songs, "Perfect" holds at its No. 2 high (125 million in audience, up 6 percent, in the week ending Dec. 24).
"Perfect" Still No. 1 on Billboard Hot 100
Sheeran and Beyoncé's "Perfect" (on Atlantic Records) tops the Hot 100 for a second week. First released as a solo song by Sheeran on his album ÷ (Divide), which debuted atop the Billboard 200 dated March 25, the new duet version was released Nov. 30. In its second full tracking week, it sold 98,000 downloads (down 46 percent), as it spends a third week at No. 1 on the Digital Song Sales chart.
"Perfect" pushes 3-2 on Radio Songs (117 million in audience, up 13 percent, good for the Hot 100's top gain in airplay) and bullets at No. 3 on Streaming Songs (39.7 million U.S. streams, up 14 percent).
Ed Sheeran & Beyonce's 'Perfect' Tops Billboard Hot 100
Ed Sheeran and Beyoncé's "Perfect" crowns the Billboard Hot 100 (dated Dec. 23), fueled in large part by the first full week of sales for its new duet version.
"Perfect," released on Atlantic Records (and the 1,069th No. 1 in the Hot 100's history, which dates to its Aug. 4, 1958, launch), was first released as a solo song by Sheeran on his album ÷ (Divide), which debuted atop the Billboard 200 dated March 25. On Nov. 30, at 7 p.m. ET, the new duet version was released, hours before the end of the sales and streaming tracking week. In its first full tracking week, ending Dec. 7, the song sold 181,000 downloads, up 202 percent, according to Nielsen Music, as it spends a second week at No. 1 on the Digital Song Sales chart.
Plus, as the duet version accounts for 63 percent of the song's total sales for the week, Beyoncé has been added on the Hot 100 (and related charts) as a co-lead artist on "Perfect." (For chart purposes, both versions of "Perfect" contribute to the song's singular listing on the Hot 100.)
"Perfect" flies 11-3 on the Streaming Songs chart with 34.9 million U.S. streams, up 87 percent, in the tracking week ending Dec. 7, while, on Radio Songs, it pushes 4-3 (102 million in audience, up 14 percent, in the week ending Dec. 10).
'Perfect' Aiming for No. 1 on Billboard Hot 100
Ed Sheeran and Beyoncé's "Perfect" could top next week's Billboard Hot 100 (dated Dec. 23), fueled most heavily by a hefty first full week of sales for its new duet version.
On this week's Hot 100 (dated Dec. 16), "Perfect" pushes from No. 5 to a new No. 3 high, aided by a partial first day of impact from the new version. It ranks below Post Malone's "Rockstar," featuring 21 Savage, at No. 1 for an eighth week, and Camila Cabello's "Havana," featuring Young Thug, at its No. 2 peak for a fifth frame.
Highlights of next week's Hot 100, which blends streaming, airplay and sales data, according to Nielsen Music, will post on Billboard.com Monday (Dec. 11).
"Perfect" was first released as a solo song by Sheeran on his album ÷ (Divide), which debuted atop the Billboard 200 dated March 25. Last Thursday, Nov. 30, at 7 p.m. ET, the new duet version was released, hours before the end of the sales and streaming tracking week. In the tracking week ending tonight, Dec. 7, the song should sell 160,000 or more downloads, according to preliminary data. Such a sum could be enough to propel "Perfect" past "Rockstar" and crown the Hot 100.
For chart purposes, both versions of "Perfect" will contribute to the song's singular listing on the Hot 100. Additionally, following the first full week of tracking for the duet version, which could account for two-thirds of the song's sales in the week, Beyoncé will be added on the Hot 100 as a credited artist on "Perfect."
"Perfect" Duet is heading for Number 1 in the UK
Ed Sheeran is set to claim his fourth Number 1 on the UK Official Singles Chart as his latest single Perfect - newly re-worked as a duet with Beyonce - leads the way on the Official Chart Update.
Perfect originally entered the chart at Number 4 back in March, when he released his ÷ album. Last week the track matched its original peak after being given an official single release, and is now set to take this week's top spot after putting out a new version of the song with Beyonce.
If Perfect holds at Number 1, it will become Ed's fourth UK chart topper following Sing, Thinking Out Loud and Shape of You.
Beyoncé Tops Forbes' Highest-Paid Women in Music List
Shortly after Adele took home the Grammy award for Album of the Year in February, she broke it in half--with the intention of physically sharing it with Beyoncé, the internet concluded—in recognition of the latter's Lemonade. But Queen Bey won an even more valuable distinction outright: she's this year's highest-paid woman in music, pulling in a whopping $105 million pretax.
Lemonade was a hit with both critics and fans, giving Beyoncé her sixth solo No. 1. The ensuing Formation World Tour, much of it falling into our list's scoring period, grossed a quarter of a billion dollars. Then she took time off as she and husband Jay-Z welcomed twins Rumi and Sir this summer. Adele finished second, earning $69 million, boosted by seven-figure nightly grosses on her first proper tour since 2011.
In order to form our list, we looked at pretax income from June 1, 2016 through June 1, 2017, and did not take out fees charged by agents, managers and lawyers. We gathered data from Nielsen SoundScan, Pollstar, the RIAA and interviews with industry insiders. The two mononymous stars both earned tens of millions more than the rest of the pack, but there are plenty of notable names further down the list.
"Walk on Water" Debuts at No. 7 in the UK
Camila Cabello has fought off challenges from Rita Ora and Eminem to score a third week atop the Official UK Singles Chart with Havana.
Thanks to a new remix featuring Daddy Yankee, and the original Young Thug version still proving popular, Havana finishes 8,000 ahead of nearest competitor Rita Ora. Rising to Number 2, Anywhere is Rita's third Top 10 single this year and her highest chart placing since I Will Never Let You Down topped the Official Singles Chart in May 2014.
Highest new entry this week comes from Eminem and Beyoncé at Number 7. Walk On Water becomes Eminem's 28th UK Top 10, and Beyonce's 19th as a credited performer.
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Have you picked up a copy of '4' yet?
by Klaudia
News & Rumors, Music, Charts, Rankings & Ratings
Beyoncé's brand new album is out and dominating the iTunes charts! 4 is already #1 on iTunes in the US and UK, France, Denmark, Ireland, Italy, Portugal, Spain, and Switzerland! Are you one of the people that pushed 4 up the iTunes charts? If not, get 4 today from iTunes and dive into the album that Ryan Dombal of Pitchfork says "has one of the world's biggest stars exploring her talent in ways few could've predicted", as well as the stunning, interactive artwork included with your download! That's not all! In celebration of the new release, Beyoncé's past hit singles are on sale for $.69 and her past albums start from $7.99. Head to iTunes and complete your Beyoncé collection.
Who Run The Charts? Beyoncé!
Beyoncé's fourth solo album 4 is now out in much of the world. From Australia, Great Britain, and France to South Africa, Argentina, and the Philippines, it's storming up the charts. Upon release, the album shot to #1 on the iTunes charts in countries across the map including Belgium, Ireland, the Netherlands, Switzerland, France, Great Britain, and Portugal.
Beyoncé's Glastonbury set brings in top ratings for BBC Two
News & Rumors, Performances, Charts, Rankings & Ratings
Those who follow us on Twitter and like us on Facebook probably would have noticed us raving about Beyonce on BBC Two last night, and unsurprisingly we weren't the only fans of the current Queen of Pop. An unusual and controversial choice to headline the third day of the festival, Beyonce certainly got viewers watching from home. A peak audience of around 2.5 million viewers tuned into BBC Two from 10PM to watch Beyonce's set, which included a cover of Kings of Leon track 'Sex on Fire'. Coverage of the last day of the weekend averaged 1.2 million between 10PM and 2AM last night on the channel.
"Run The World (Girls)" Passes 40 Million Views On VEVO
Earlier this week, Beyoncé fans pushed total views of the "Run The World (Girls)" music video past 40 million on VEVO! The video, which was released just shy of a month ago and premiered on American Idol in the US and Canada, has already become Beyoncé's fourth most watched video on VEVO. If you haven't seen it yet, we're not sure where you've been hiding, but you can watch it here. Don't have the song yet? Download it here.
Beyonce voted most desirable bikini-clad rear of 2011
News & Rumors, Charts, Rankings & Ratings
Beyonce's curves have fetched her the top position in a poll, set to find the most desirable bikini-clad rear of the year. The 29-year-old 'R and B' babe narrowly beat recording rival 23-year-old Rihanna. "I work hard to stay in shape, so I'm flattered my efforts are being noticed," the Daily Star quoted 'The Best Thing I Never Had' singer as saying. She edged out 'Fantastic Four' and 'Sin City' stunner Jessica Alba, who came third. Pop princess Britney Spears, 29, came fourth. Cameron Diaz, 38, was fifth in the poll of 45,000 viewers carried out by a US cable TV network.
Jay-Z Beats Out Beyonce For Money Earned This Year
Forbes reports that Jay-Z earned more money than his superstar wife for the first time since they married in 2008. During the past 12 months, Forbes reports, Jay-Z pulled in $37 million--$2 million more than wife Beyonce Knowles. This is the first time Jay has earned more than his wife since they married back in 2008. While Jay's 40/40 Club, his stake in the New Jersey Nets, and his bestselling book Decoded all contributed to his earnings this past year, it's his 10-year, $150 million deal with Live Nation that has been the most lucrative. Beyonce's deals with Nintendo, L'Oreal, as well her own clothing line House of Dereon, are huge factors in her $35 million earnings in the previous 12 months. Both artists earned substantially less than they did last year ($63 million and $87 million respectively) due to the fact that both did a smaller amount of touring this year. The pair did not release any albums since the last Forbes cycle, but are expected to later on in the year. Interestingly enough, Forbes reports, neither made as much as Justin Bieber, who raked in $53 million this year.
Beyonce Blows Up Social 50 Chart
Skyrocketing 25-14 on Billboard's Social 50 chart, Beyoncé rallies to a new chart high with a 334% burst in new week-over-week plays on monitored social networks and 142% boost in views. The jump is owed to attention gained from her new single "Run the World (Girls)," the diva's first single from her forthcoming fourth studio album. "Run the World" has earned 1.46 million YouTube views since its YouTube premiere April 21, and also lands at No. 33 on this week's Billboard Hot 100. As well, Beyoncé released a video in support of First Lady Michelle Obama's campaign against childhood obesity called "Move Your Body." While neither song is on Vevo, other Beyonce videos on the site did see a 340% surge in plays. The Social 50 ranks the most active artists on the world's leading social networking sites -- YouTube, Vevo, Facebook, Twitter, MySpace and iLike -- using a formula blending weekly additions of friends/fans/followers along with weekly artist page views and weekly song plays.
Beyoncé's 'Run the World' Makes Chart Debut
Beyoncé returns to the charts with her first single of 2011. "Run the World (Girls)," the lead offering from the pop powerhouse's fourth album, lands at No. 33 on this week's Billboard Hot 100. Additionally, the Major Lazer-sampled tune logged 77,000 downloads since arriving in the iTunes store last Thursday, bowing at No. 23 on the Digital Songs chart. On radio, Bey is getting some love, beginning at No. 65 on the Radio Songs chart with a respectable 18 million in audience. The highly-anticipated video for the Switch-produced female anthem was shot over several days in California with director Francis Lawrence and will debut sometime in May. Elsewhere on the Hot 100, Lady Gaga's "Judas" drops two spots after debuting at No. 10 last week, while Katy Perry and Kanye West's "E.T." returns to the top for a fourth week.
Run The World (Girls) is #18 in the UK charts
The song Run The World (Girls) by Beyoncé has been listed for 1 week on the UK Singles Top 75. It entered the chart on position 18 on week 17/2011. Congratulations!
Top-selling celebrity perfumes
News & Rumors, Fragrances, Charts, Rankings & Ratings
Would you want to smell like Derek Jeter? How about Jessica Simpson or Beyoncé? Celebrity scents might not reflect the actual smells of our favorite stars, but they do represent a connection to those celebrities that can be quite lucrative for the companies that partner on the scents. The top 10 bestselling celebrity perfumes from 2010 brought in $215 million in the U.S., according to Euromonitor International. Celebrity fragrances are more popular than ever. Just this year we've seen scents launched by Katy Perry, Fergie, Rihanna and Kim Kardashian. Companies like Coty, Elizabeth Arden and Avon like to partner with celebrities on new fragrances because they are great marketers. "Companies feel it's a great way to reach younger consumers in the U.S.," says Virginia Lee, senior research analyst at Euromonitor. "Somewhere like France, putting on fragrance in the morning is a daily habit. In the U.S. fragrance has never completely taken hold." Celebrities are naturally in the spotlight as often as possible, and they come with built-in fan bases that often want to buy the perfume regardless of how it smells. Singer Mary J. Blige recently launched her first fragrance, My Life, on the Home Shopping Network. "The fact that people are buying a fragrance without even smelling it says there's a connection with the celebrity," says Lee. Celebrities can also use their fan base to cheaply spread the word about a scent. When Rihanna launched her Re'l Fluer perfume in February she put out a one-minute video that quickly made the rounds among her 4.5 million Twitter followers and 30 million Facebook fans. Topping our list this year is White Diamonds by Elizabeth Taylor. Elizabeth Arden sold $54 million worth of the scent in the U.S. last year. Lee, of Euromonitor, says the scent appeals to baby boomers who associate Taylor with the glamour of her youth. But the perfume also has an appealing smell; it's been a bestseller since it hit stores in 1991. Read more...
Beyoncé's assets win the vote
Singer Beyoncé is the celebrity with the best body in the eyes of British women, but males prefer Hollywood actress Megan Fox. The singer topped the poll among females, with 24 percent of the vote, but one in five men stated Transformers star Fox boasted the sexiest body and named her as the woman they would most like to sleep with if their partner gave them a celebrity pass. The poll of 2 000 people also revealed newlywed Katie Price was losing favour with the public, with a third of men and women unanimously naming her as the least attractive celebrity. Slim-figured Victoria Beckham did not fair well among those questioned, being voted the celebrity with the worst figure by both sexes. The attractiveness study, conducted by Twentieth Century Fox Home Entertainment to mark the Blu-ray release of Jennifer's Body, starring Fox, found that as well as being women's overall body choice, Beyoncé boasted the sexiest individual assets. About 34 percent of men and women surveyed named her as the celebrity with the best bottom, while a quarter of respondents said she had the best legs. Beyoncé's bosom also topped among women, with 23 percent saying she had the best celebrity cleavage. Hollywood siren Angelina Jolie and Fox shared first place among male voters in this category, both attracting 19 percent. British actress Keira Knightley took the crown for the prettiest face with 18 percent of both men and women putting her top of the list, while Jennifer Aniston secured 17 percent. Aniston was head and shoulders above the field in the celebrity hair category, polling 35 percent of all votes.
Beyonce, Kim K, And J. Lo Top Playboy's Sexiest Celebrities List
R&B superstar Beyonce, reality star Kim Kardashian and actress/singer Jennifer "J.Lo" Lopez have all topped the list in Playboy's new Sexiest Celebrities List. The list includes 27 women, who range from being an actress, singer, reality star and model. According to Playboy, the foxy and famous starlets were chosen because "they exude the radiance of experienced women who remain on top of their game." Check the full list below:
Natalie Portman, Hope Dworaczyk, Sophie Monk, Tara Reid, Brooke Burke, Anna Paquin, Kendra Wilkinson, Halle Berry, Candice Boucher, Arianny Celeste, Sasha Grey, Jennifer Lopez, Kelly Brook, Michelle Williams, Holly Madison, Beyoncé, Amber Heard, Kim Kardashian, Pamela Anderson, Jenni "JWoww" Farley, Angelina Jolie, Claire Sinclair, Crystal Harris, Christina Hendricks, Megan Fox and Olivia Wilde.
5 Best Singers/Dancers in Pop Music Today
#5. Ciara
The R&B star maximized her krumping skills as the genre swept American in the early 00's -- but while subsequent styles have bumped the frenetic full body spasm out of popular favor, her "music" has similarly suffered. Bottom line: she's one fresh face away from being permanently cut from this list
Best Moves: "1, 2 Step" video
#4. Lady GaGa
Forging an early bond with choreographer du jour Laurieann Gibson has served GaGa well over the last three years as she's eschewed standard moves for more atypical, yet no less popular, creations.
Best Moves: "Bad Romance" at The 2009 AMA's
#3. Rihanna
Although she's been making club-banging dance music since the jump, Rihanna's career wasn't predicated on being able to shake that ass like her fans do. This all changed with the release of her latest CD, "Loud" and the gyration-heavy performances she's been serving up with "What's My Name."
Best Moves: "What's My Name" at the 2011 Grammys
#2. Nicole Scherzinger
When you front a group born out of a burlesque dance club, odds are you can slam it to the ground and shake it all around with the best of them. But the biggest surprise about the Pussycat Dolls' queen bee has been her consistent ability to serve up hard-hitting routines while singing live.
Best Moves: "When I Grow Up"
#1. Beyonce
Was there any doubt B would snag the top slot? If you thought otherwise, I don't know what you've been doing for the last 15 years, but it certainly wasn't watching a single live performance -- be it in concert or on television -- as the megastar consistently devoted every ounce of her to the routine. And the fact she was able to do it night after night on her seemingly endless I Am Sasha Fierce Tour makes Beyonce's professionalism and skill all the more impressive,
Best Moves: "Single Ladies" on 2008 AMA's
Beyonce Makes '50 Most Beautiful In Film'
News & Rumors, Movies, Charts, Rankings & Ratings
What do Natalie Portman, Blake Lively and Beyoncé Knowles have in common with iconic Hollywood royalty like Marilyn Monroe, Vivien Leigh and Faye Dunaway? Well, they're all talented, accomplished and, of course, stunningly beautiful. With the Oscars just around the corner, the Los Angeles Times Magazine compiled a list of the 50 Most Beautiful Women in Film, celebrating how these stars "set the standard for grace, glamour and allure." The magazine admits to being "totally biased" in their selections, and it made for some surprising results. Landing in the top five are Academy Award winners Kim Basinger (#3) and Halle Berry (#5). The Times noted Basinger's sexy turn as a prostitute employed as an actress look-alike in "L.A. Confidential" as an example of her best and sexiest work, while Berry easily captured her spot thanks to her Oscar win for "Monster's Ball" and her turn as a Bond girl in "Die Another Day." While love from the Academy wasn't a requirement, many of the beauties on the list have some Oscar credentials. A 2011 Best Actress nominee for her turn in "Black Swan," Natalie Portman took the #39 slot, while "Gossip Girl" star Blake Lively (the youngest woman on the list) was honored with a spot at #30 thanks to her roles in "Sisterhood of the Traveling Pants" and the upcoming "Green Lantern." "American Idol" judge Jennifer Lopez follows behind Lively at #31. Jennifer Connelly landed at #9, with her Oscar win for "A Beautiful Mind" and her glamorous turn in 1996's "Mulholland Falls" as evidence of her talent. "Pirates of the Caribbean" star and fellow Oscar-winner Penelope Cruz followed her at #11. This year's Oscars co-host, Anne Hathaway, earned the #19 ranking, making the 28-year-old actress the youngest on the list in the top 20. Rounding out the top 20 is Salma Hayek, whose "Wild Wild West" was cited as her sexiest work. Angelina Jolie placed surprisingly low at #23, with classic Hollywood actress Grace Kelly placing right behind her at #24. Beyoncé made something of a surprise appearance on the list at #25, largely thanks to her work in 2006's "Dreamgirls"; the singer/actress was recently cast in Clint Eastwood's "A Star Is Born" remake. Hollywood A-listers also making the list include "Slumdog Millionaire" star Freida Pinto (#38), Julia Roberts (#40), Charlize Theron (#45), Rachel Weisz (#48) and Catherine Zeta-Jones (#50).
Most popular celeb names for dogs
Cheryl Cole has been voted as the celebrity after whom most people would like to name their dog. The top five female names people would like to give their pooches are Cheryl, Posh, Lady Gaga, Grace Kelly and Beyonce. Meanwhile, in a poll for male celebrity names for dogs, the list had Ozzy at number one, followed by Boris, Arnie, Elvis and Bono. The top traditional names for canines were revealed as Alfie, Buster and Barney. The poll was comissioned by National Geographic for its Nat Geo Wild channel.
Beyonce named Woman of the Decade by AskMen
Making a huge jump since last year from number 85, Blake Lively, 23, has scored the number one spot in AskMen's List of Top 99 Most Desirable Women of 2011. This actress has blown away fans everywhere, with hit television show Gossip Girl, and movies like The Town and Green Lantern,, which is soon to be released. AskMen stated they were most attracted to her "unusual amount of dignity and composure." This list reached its 10th anniversary this year. There were several new additions, and there were surprises in women who have been on in the past, but not this time. Beyonce, who was announced as Woman of the Decade, dropped down to number 23. Other women who were considered "most desirable" were Gisele Bundchen, Angelina Jolie, Sofia Vergara, and Mila Kunis.
Beyonce On Top of Most Coveted Body List
In The Devil Wears Prada, fledgling magazine assistant Andy is informed that size two is the new size four, and size zero is the new size two. Well it seems size six (UK size 10) Andy, played by Anne Hathaway in the film, had the last laugh, as eight in 10 women now aspire to the curves of Mad Men star Christina Hendricks, according to research published today. It found that modern women no longer consider Victoria Beckham's fashion-thin build the 'perfect figure', and 80 per cent of women would now prefer a fuller shape, like that of model Kelly Brook or singer Beyoncé. Only 20 per cent of the 60,000 women, surveyed by Look magazine, admitted that they preferred a slimmer body shape. Over nine in ten said they felt women of all sizes could be stylish and a further six in ten wanted to see more pictures of 'real' women in fashion magazines. Ali Hall, editor of the magazine, said: 'Five months ago Look started using curvier models in the issue every week and the response was overwhelming. 'Now 94 per cent of our readers believe that women of all sizes can be fashionable and it's important that the magazine reflects this.' Beyoncé and model Kelly Brook came a joint first in the list of celebrity bodies readers would most like to look like. They were followed by singer Rihanna, reality television star Kim Kardashian and Christina Hendricks. Kate Moss, fashion designer Victoria Beckham, Kylie Minogue, Twilight actress Kristen Stewart and supermodel Gisele Bundchen emerged as the least popular.
Beyonce & Jay-Z Cover Ebony As One Of 'The Hottest Couples'
News & Rumors, Photos, Magazines, Charts, Rankings & Ratings
Jay-Z and his wife Beyonce have been pictured as one of the "hottest couples" in celebrity by Ebony magazine. The superstar couple grace the cover of one of three special covers which also features president Barack Obama and the first lady Michelle Obama. Another couple pictured are actors Boris Kodjoe and Nicole Ari Parker, the pair worked together on the US TV series 'Soul Food'. Other couples who have been listed in the top 15 couples include Swizz Beatz and Alicia Keys, T.I. and Tiny, Will Smith and Jada Pinkett-Smith - but they didn't make the covers...
AskMen's Top 99 Most Desirable Women
Charts, Rankings & Ratings
Who is the most desirable woman of 2011? It's your turn to help AskMen decide. AskMen's annual list of the Top 99 Most Desirable Women ranks the famous females who rock our world -- from stand-up comediennes and powerful businesswomen to Oscar-bound actresses and swimsuit models. Will Emmanuelle Chriqui be able to hold on to her No. 1 spot? That's where you come in. Scroll over the women in the three categories we've provided and give as many candidates as you like a score between 1 and 10 (10 being the most desirable; 1 being the least). The voting period starts now. Click here to vote for Beyonce.
Beyonce Out-Earns Britney Spears, Lady Gaga
The term "music mogul" usually conjures up someone like Jay-Z, but it turns out his wife, Beyonce, has got everyone beat. Beyonce tops Forbes magazine's new list of Hollywood's top-earning "entertainment moguls in the making" -- a roundup of celebrities at or under the age of 35 who make money from multiple revenue streams. Beyonce took in a $87 million between June of 2009 and June of 2010, thanks to her income from touring and recording, plus her TV specials, movies, fashion line, fragrance and her endorsement deals with the likes of L'Oreal and Nintendo. Number two on the list was Britney Spears, who made $64 million in a similar period thanks to a concert tour, her line of best-selling perfumes and her endorsement deal and clothing line for Candie's. Lady Gaga came in third, raking in $62 million thanks to her sold-out Monster Ball tour, her record sales, her deals with Polaroid, Virgin Mobile and Monster Cable, and all those product placements in her videos. Fourth on the list was Miley Cyrus, who brought in $48 million through her touring, movie roles and merchandise. Taylor Swift was number five, thanks to her endorsement deals with Cover Girl and Sony, as well as her record-breaking album sales.
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1.19 +/- acres of Linear Commercial Corridor property, located just north of Downtown Winter Haven on US 17. All utilities are located at the site or adjacent to the site . Excellent visibility as well as full access via two side roads.


How often should I schedule my lessons?
In short, as often as possible! We offer several packages with 1-3 lessons per week; and additional lessons may be scheduled at any time. Individual lessons may be scheduled; however, weekly consistency is paramount to finishing our program efficiently.
Please see our service menu for all pricing.
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Tuition is due in full at the beginning of each month and may be paid online (bank transfer/credit/debit) or by check.
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text:
Q: Thread-safe design with ARC First of all let me quote a chapter from Apple Threading Programming Guide:

Be Aware of Threats to Code Correctness
When using locks and memory barriers, you should always give careful thought to their
  placement in your code. Even locks that seem well placed can actually
  lull you into a false sense of security. The following series of
  examples attempt to illustrate this problem by pointing out the flaws
  in seemingly innocuous code. The basic premise is that you have a
  mutable array containing a set of immutable objects. Suppose you want
  to invoke a method of the first object in the array. You might do so
  using the following code:

NSLock* arrayLock = GetArrayLock();
NSMutableArray* myArray = GetSharedArray();
id anObject;

[arrayLock lock];
anObject = [myArray objectAtIndex:0];
[arrayLock unlock];

[anObject doSomething];

Because the array is mutable, the lock around the array prevents other
  threads from modifying the array until you get the desired object. And
  because the object you retrieve is itself immutable, a lock is not
  needed around the call to the doSomething method.
There is a problem with the preceding example, though. What happens if
  you release the lock and another thread comes in and removes all
  objects from the array before you have a chance to execute the
  doSomething method? In an application without garbage collection, the
  object your code is holding could be released, leaving anObject
  pointing to an invalid memory address. To fix the problem, you might
  decide to simply rearrange your existing code and release the lock
  after your call to doSomething, as shown here:

NSLock* arrayLock = GetArrayLock();
NSMutableArray* myArray = GetSharedArray();
id anObject;

[arrayLock lock];
anObject = [myArray objectAtIndex:0];
[anObject doSomething];
[arrayLock unlock];

By moving the doSomething call inside the lock, your code guarantees
  that the object is still valid when the method is called.
  Unfortunately, if the doSomething method takes a long time to execute,
  this could cause your code to hold the lock for a long time, which
  could create a performance bottleneck.
The problem with the code is not that the critical region was poorly
  defined, but that the actual problem was not understood. The real
  problem is a memory management issue that is triggered only by the
  presence of other threads. Because it can be released by another
  thread, a better solution would be to retain anObject before releasing
  the lock. This solution addresses the real problem of the object being
  released and does so without introducing a potential performance
  penalty.

NSLock* arrayLock = GetArrayLock();
NSMutableArray* myArray = GetSharedArray();
id anObject;

[arrayLock lock];
anObject = [myArray objectAtIndex:0];
[anObject retain];
[arrayLock unlock];

[anObject doSomething];
[anObject release];

And the question is: Is there any way to solve the problem while using ARC?

A: ARC solves this problem for you automatically; by default every pointer is a strong pointer, which means that the object is guaranteed to be retained until you are done using that pointer.
This means that whenever you get an object out of an array, ARC always retains that object. This guarantees its lifetime, even if the object is later removed from the array.

redpajama_set_name: RedPajamaStackExchange


When merge is in progress engine writes changes into both delta and main file. This creates additional IO load of course.
e) page is read from delta, this copy have no changes by (b) !
change page marked with BDB_merge flag. Note, this optimization not applicable for Classic.
Solution is to undo such optimization. Another way to avoid double writes could be implemented but not in this ticket.
Vlad Khorsun added a comment - 05/May/11 06:19 PM - edited Classic is not affected as there is no other activity except of merge itself in the same page cache instance. I.e. there is no user process which could change page marked with BDB_merge flag. Note, this optimization not applicable for Classic. Solution is to undo such optimization. Another way to avoid double writes could be implemented but not in this ticket.


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In a world that has become a helpless victim of the corporate monotony, a balanced and a healthy lifestyle appears to be a far-fetched dream. With varied opinions floating around to cope up with the millennial lifestyle, which health advice should we rely on? As individuals, we're always on the lookout for information that is based on a validated expertise. The upcoming season of Trust Me I'm a Doctor on Sony BBC Earth helps you lead a healthy life, amidst the many health claims.
Presented by well-known medical journalist Dr Michael Mosley, Trust Me I'm a Doctor S7 finds out the truth about what's good for your health with five surprising discoveries.
They are right when they say that laughter is the best medicine. With stress and mental health problems becoming a major concern these days, it is proven that laughter leads to the release of endorphins which are anti-depressant. Also, consuming products like walnuts and fish oil release hormones that reduce anxiety and depression.
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All mothers believe green vegetables are incredibly beneficial and inculcate the same habit in the family members. However, there's another vegetable that proves to be healthy. It is the beetroot — which is claimed to improve both our physical health and mental sharpness. On a three level test conducted by the researchers in the show, it was proved that beetroot helps in effective mental performance, reduces fatigue and regulates an intensive blood pressure.
When you think of vital nutrients your body might be short of, perhaps iron springs to mind or vitamin C. But there is another which doesn't make the headlines as much as it should — iodine. Iodine is absolutely essential to our health. It's used by the thyroid gland to produce hormones that keep your body working normally. Having low levels of these hormones is linked to weight gain, fatigue and mood swings. Two of the most essential sources of iodine are milk and white fish. A detailed experiment in the show proves that our bodies can easily absorb iodine from these two sources which are easily available. Solves the problem, right?


text:
\section{Introduction}  \label{intro}

\IEEEPARstart{E}{FFECTIVE} detection of unknown signals has been  a critical research topic since  it is  typically encountered in  applications relating to RADAR,  cognitive radio and ultra-wide band systems. Energy detection (ED) has been the most widely considered detection method due to its non-coherent structure and low implementation complexity \cite{J:Alouini}  and the references therein.  Its operation is based  on the deployment of a radiometer that its  output decision is determined by comparing the received energy level with a reference energy threshold. In the context of cognitive radio, this  decision indicates the presence or absence of unknown  signals, while the overall detection capability has been typically characterized by  the corresponding probability of detection, $P_d$, and probability of false alarm, $P_f$ \cite{J:Alouini}. Since the  objective in such systems is not  information recovery, the process is solely based on the amount of its energy regardless of its other parameters, such as carrier phase information. Therefore, in the context of ED, an unknown signal is defined as a deterministic signal with an unknown form, which can be considered a sample function of a random process. However, knowledge of the spectral region to which its confined  along with the estimated SNR statistics are sufficient to allow design of suitable energy detectors  \cite{Paschalis_1}.
\par   It is also known that fading effects create detrimental impacts on the performance of conventional and emerging communication systems \cite{Additional_1, Additional_2, Additional_3, Additional_4, Additional_5, Additional_6, Additional_7, Additional_8, Additional_9}.  Based on this and capitalizing on the fundamental contribution of \cite{J:Alouini}, numerous investigations  have been reported on the performance and behavior of ED in various practical scenarios.  Specifically,   thorough analyses  over multipath and composite   fading channels, were carried out  for both single-channel and multi-channel scenarios  in \cite{Maged, Paschalis_1, Paschalis_2, Paschalis_4, Paschalis_5, Paschalis_6, Paschalis_7, Paschalis_8} and the references therein. In the same context,  the performance over  hyper Rayleigh  conditions was analyzed in \cite{Hu}.  Nevertheless, in spite of the usefulness of the reported analyses, none of them  accounts for the case of  cascaded fading channels. The detrimental effects   in such  fading conditions are because   transmitted signals are exposed to a product of a large number of rays reflected by $N$ statistically independent scatterers. For example, it is practically demonstrated in \cite{Frolik}   that cascaded channels can accurately model the abrupt and rapid fading dynamics resulting from large mobile scatterers in inter-vehicular communications.

Cascaded fading conditions are also encountered in   scenarios such as  multihop cooperative communications and multiple-input-multiple-output (MIMO) keyhole communications systems \cite{Karagiannidis}. In multihop relay cognitive radio networks, ED is performed by cooperative sensing, where the process of detecting the primary signal is replicated through a number of multihop sensing nodes by means  of non-regenerative relaying. Similarly, in the case of keyhole  MIMO channels, a multi-antenna secondary user employs ED to sense the spectrum of a multi-antenna primary user \cite{Zhan}. Likewise, cognitive vehicular networks (CVNs) have been proposed as an effective  method to provide adequate and robust operation in daily road traffic, and thus, vehicular nodes have to be equipped with efficient spectrum sensing capabilities \cite{Felice}.

Motivated by the above, the present work quantifies the behavior  and performance of ED under  cascaded Rayleigh fading conditions for both single-channel and multi-channel scenarios. This topic was partly addressed in \cite{Ilhan} by deriving an infinite series, which was  not studied in terms of accuracy and convergence. On the contrary, in the present analysis, a novel analytic expression is firstly derived  for an infinite integral involving a product of a Meijer $G-$function, a  Marcum $Q-$function and power terms. This solution is generic and is anticipated to be useful in various analyses relating to  natural sciences and engineering. To this end, it is employed in the derivation of an exact closed-form expression for the $\overline{P}_{d}$ of ED  over $N$ cascaded Rayleigh channels. The derived  expression is subsequently employed in extending the offered results  to the case of square-law selection, which is a relatively simple and robust diversity method that exhibits improved performance.

\IEEEpubidadjcol

\section{ Channel and System Model }

\subsection{ The $N$*Rayleigh Fading  }

 It is recalled that multiplicative fading models are capable of accounting  for fading phenomena holistically \cite{Karagiannidis}.  Physically,  these models consider received signals generated by the product of a
large number of rays reflected via $N$ scatterers \cite{Karagiannidis, Frolik}. Based on this, a generic  cascaded fading model, so called $N$*Nakagami$-m$,  was proposed in \cite{Karagiannidis} that is constructed by the product of $N$ statistically independent but not necessarily identically distributed Nakagami$-m$ random variables.  When $m=1$, this model reduces to the $N$*Rayleigh distribution  with probability density function (PDF)

\begin{equation} \label{Cascaded}
p_{\gamma}(\gamma) =  \frac{1}{\gamma } G_{0, N}^{N, 0} \left[ \frac{\gamma}{\overline{\gamma}} \left| ^{  \, \,  \quad \, \, \, \,  \,   -     }_{\underbrace{1, 1, \cdots, 1}_{N}} \right. \right]
\end{equation}
where $\gamma$ and $\overline{\gamma}$ denote the instantaneous and average signal-to-noise ratio (SNR), respectively and  $G(\cdot)$  is the Meijer $G$-function.
For the special case that $N=2$, $N$*Rayleigh  reduces to the double Rayleigh fading model, which has been used to model fading conditions in realistic communication scenarios, including mobile transmitter and receivers  \cite{Frolik, Hu}. It is also noted that cascaded fading models  have been  used in modeling the keyhole channel in multi-antenna systems \cite{Karagiannidis}.

\subsection{Energy Detection of Unknown Signals }

The detection  of unknown signals can be  modeled as a binary hypothesis-testing problem, where $H_0$ and $H_1$ correspond to the cases that a  signal  is absent or present, respectively.  Based on this, the received signal   can be expressed as \cite{J:Alouini}

\begin{equation}\label{eq:System_model_1
y\left(t\right) = \left\{ {\begin{array}{*{20}{c}}
{n\left(t\right)}&{:{H_0}}\\
{hs\left(t\right) + n\left(t\right)}&{:{H_1}}
\end{array}} \right.
\end{equation}
where $h$ and ${s\left( t \right)}$ denote the wireless channel gain and  the transmitted information signal  with average power $E_s$, respectively, and  ${n\left( t \right)}$ is the  zero-mean complex additive white Gaussian noise (AWGN) with single-sided power spectral density $N_0$. The received signal is firstly band-pass filtered at bandwidth $B$ (Hz) and the output of the filter is subsequently squared and integrated over time duration $T$. This generates the test statistic $Y$ which is typically formulated as \cite{J:Alouini}

 \begin{equation}\label{eq:ED_1
Y \sim \left\{ {\begin{array}{*{20}{c}}
{\chi _{2u}^2}&{:{H_0}}\\
{\chi _{2u}^2\left( {2\gamma } \right)}&{:{H_1}}
\end{array}} \right.
\end{equation}
where $\chi _{2u}^2$ is  a central chi-square distribution with $2u$ degrees of freedom with $u$ denoting the corresponding time-bandwidth product. Likewise, ${\chi _{2u}^2\left( {2\gamma } \right)}$ is  a non-central chi-square distribution with the same degrees of freedom and a non-centrality parameter $2\gamma$, with $\gamma  = {\left| h \right|^2} {{E_s}}/{{N_0}}$ denoting the  instantaneous SNR of the target signal. Finally, the test statistic $Y$ is compared with an energy threshold $\rm{\lambda }$, which  determines the absence or presence of the signal under test  \cite{J:Alouini}. In the case of AWGN, the  probability of false alarm and probability of detection are represented  as  follows

\begin{equation}
{P_f} = {\rm Pr}\left( {Y > \lambda |{H_0}} \right) = G\left( {u, \frac{\lambda}{2}} \right)
\end{equation}
and

\begin{equation}
{P_d} = {\rm Pr}\left( {Y > \lambda |{H_1}} \right) = {Q_u}\left( {\sqrt {2\gamma } ,\sqrt \lambda  } \right)
\end{equation}

respectively, where   $G\left( a, b\right)$ and ${Q_u}\left( {a,b} \right)$ are  the regularized upper incomplete gamma function and the   Marcum $Q-$function, respectively.

\section{Energy Detection  over $N$*Rayleigh Channels }
\label{analytic}

Meijer$-G$ and Marcum$-Q$ functions are particularly important in wireless communications. However, to the best of the authors' knowledge, no tabulated  solutions for integrals that involve a product of a Meijer $G-$function, a Marcum $Q-$function and arbitrary power terms exist in the literature.

\begin{theorem}
For $t \in \mathbb{R} $,  $u, b, c \in \mathbb{R}^{+}$, $m, n, p, q \in \mathbb{N}$, and $G(\cdot ,\cdot)$ denoting the bivariate Meijer G-function, equation \eqref{solution}  is valid for the   integral:

\begin{equation}  \label{integral_problem}
\mathcal{I} = \int_{0}^{\infty} x^{t-1}  Q_{u}(b \sqrt{x}, c)   \,   G_{p, q}^{m, n} \left( k x \left| ^{a_{1}, \cdots, a_{n}, \,  a_{n+1}, \cdots, a_{p} }_{b_{1}, \cdots, b_{m}, \,  b_{m+1}, \cdots, b_{q}}\right.  \right) {\rm d}x.
\end{equation}

\begin{equation} \label{solution}
\mathcal{I} = -   \frac{2k}{b^{2}} G_{1, 0: 1, 3: p+1, q+1}^{0,1: 1, 0: m, n+1} \left( ^{0}_{-} \left|^{\quad 1/2}_{0, -u, 1/2}\right.  \left|  ^{1, t + a_{1}, \cdots, t + a_{n}, \,  t + a_{n+1}, \cdots, t + a_{p} }_{t + b_{1}, \cdots, t + b_{m}, \, 0, \, t +  b_{m+1}, \cdots, t + b_{q}} \right| \frac{c}{2}, \frac{2k}{b^{2}}    \right).
\end{equation}
\end{theorem}

\begin{proof}
By setting $y = kx$ in \eqref{integral_problem}  it immediately  follows that

\begin{equation} \label{integral_1}
\mathcal{I} = \int_{0}^{\infty}   \frac{ Q_{u}\left(\frac{b \sqrt{y}}{\sqrt{k}}, c \right) }{  y^{1 - t} k^{t}}     \,    G_{p, q}^{m, n} \left( y \left| ^{a_{1}, \cdots, a_{n}, \,  a_{n+1}, \cdots, a_{p} }_{b_{1}, \cdots, b_{m}, \,  b_{m+1}, \cdots, b_{q}}\right.  \right) {\rm d}y.
\end{equation}
The above integral is improper; as a result, by integrating  by parts with respect to the power term and the Meijer $G-$function using \cite[eq. (07.34.21.0002.01)]{Wolfram}, one obtains

\begin{equation} \label{integral_2}
\mathcal{I} =  \lim_{y \to \infty}   \frac{   f(y)    }{k^{t} } Q_{u}\left(\frac{b \sqrt{y}}{\sqrt{k}}, c \right) - \lim_{y \to 0}   \frac{   f(y)    }{k^{t} } Q_{u}\left(\frac{b \sqrt{y}}{\sqrt{k}}, c \right)   -    \frac{  1    }{k^{t} }  \int_{0}^{\infty} f(y)  \left\lbrace \frac{{\rm d}}{{\rm d} y} Q_{u}\left(\frac{b \sqrt{y}}{\sqrt{k}}, c \right) \right\rbrace  {\rm d}y
\end{equation}
where

\begin{equation} \label{integral_3}
f(y) =  G_{p+1, q+1}^{m, n+1} \left( y \left| ^{1, t + a_{1}, \cdots, t + a_{n}, \,  t + a_{n+1}, \cdots, t + a_{p} }_{t + b_{1}, \cdots, t + b_{m}, \, 0, \, t +  b_{m+1}, \cdots, t + b_{q}}\right.  \right).
\end{equation}
Evidently, both limits in \eqref{integral_2} approach zero, yielding

\begin{equation} \label{integral_4}
\mathcal{I} =   -    \frac{  1    }{k^{t} }  \int_{0}^{\infty} f(y)  \left\lbrace \frac{{\rm d}}{{\rm d} y} Q_{u}\left(\frac{b \sqrt{y}}{\sqrt{k}}, c \right) \right\rbrace  {\rm d}y.
\end{equation}
The derivative of the Marcum $Q-$function with respect to $y$ can be determined with the aid of  \cite{Paschalis_3}. Hence, by performing the necessary change of variables, substituting in \eqref{integral_4} along with \eqref{integral_3} and carrying out basic manipulations it follows that

\begin{equation}  \label{integral_5}
\mathcal{I} = -   \int_{0}^{\infty}  \frac{  G_{p+1, q+1}^{m, n+1} \left( y \left| ^{1, t + a_{1}, \cdots, t + a_{n}, \,  t + a_{n+1}, \cdots, t + a_{p} }_{t + b_{1}, \cdots, t + b_{m}, \, 0, \, t +  b_{m+1}, \cdots, t + b_{q}}\right.  \right)  }{ 2  c^{-u} k^{t + 1 - \frac{ u}{2} } b^{u - 2} e^{\frac{c^{2}}{2}}   y^{\frac{u }{2}}e^{\frac{y b^{2}}{2k} } \left[  I_{u}\left( b c \sqrt{\frac{y}{k}} \right) \right]^{-1} }      {\rm d}y
\end{equation}
where $I_{n}(x)$ is the modified Bessel function of the first kind.

By then expressing the $\exp(\cdot)$ and $I_{n}(\cdot)$ functions   in terms of the Meijer $G-$function, equation  \eqref{integral_6} is deduced

\begin{equation} \label{integral_6}
\mathcal{I} = 1 -   \frac{\pi b^{2} c^{2u} e^{-\frac{c^{2}}{2}}}{2^{u + 1} k^{t + 1}} \int_{0}^{\infty}  G^{1, 0}_{0,  1} \left(  \frac{b^{2} y}{2k}  \left|^{    {-} }_{0} \right. \right)   \, G^{1, 0}_{1,  3} \left( \frac{b^{2} c^{2} y}{4 k} \left|^{    \quad 1/2    }_{0, -u, 1/2} \right. \right)   G_{p+1, q+1}^{m, n+1} \left( y \left| ^{1, t + a_{1}, \cdots, t + a_{n}, \,  t + a_{n+1}, \cdots, t + a_{p} }_{t + b_{1}, \cdots, t + b_{m}, \, 0, \, t +  b_{m+1}, \cdots, t + b_{q}} \right. \right)  {\rm d}y.
\end{equation}
Importantly, this integral can be expressed in closed-form with the aid of \cite[eq. (07.34.21.0081.01)]{Wolfram}. Thus, by performing the necessary change of variables and substituting in \eqref{integral_6} yields (\ref{solution}), which completes the proof.
\end{proof}

\begin{remark}
The Meijer $G$-function of one and two variables
 is used increasingly in wireless communications and  can be evaluated numerically with the aid of  the  algorithm  in \cite[Table II]{Yilmaz}.
It is also algebraically related to the respective Fox $H-$functions  and thus \eqref{solution} can be also generically represented in terms of the  Fox $H-$function for the special case that  $ \mathcal{C} = 1$.
\end{remark}

\subsection{Average Probability of Detection in $N$*Rayleigh Fading }

As already mentioned, the generic solution in \eqref{solution} can be used in numerous applications in wireless communications.

\begin{corollary}
For $u, \lambda, \overline{\gamma} \in \mathbb{R}^{+}$ and $N \in \mathbb{N}$, the following expression holds for the average probability of detection over $N$*Rayleigh  fading channels with $G^{-1}(\cdot, \cdot)$ denoting the inverse regularized   incomplete gamma function.

\begin{equation} \label{Average_Pd}
\overline{P}_{d} =   {\huge  G}_{2,1: 1, 3: 1, N+1}^{0,1: 1, 0: N, 1} \left( ^{\frac{u}{2}, \frac{u-1}{2}}_{\, \, \, \,  \frac{u-1}{2}} \left|^{\quad \frac{1}{2}}_{0, -u, \frac{1}{2}}\right.  \left|  ^{\, \quad  \,  1 }_{1, \cdots , 1, 0, 1} \right| - G^{-1}(u, P_f), - \frac{1}{\overline{\gamma}}    \right).
\end{equation}
\end{corollary}

\begin{proof}
It is recalled that $\overline{P}_d$ is obtained by averaging  $P_d$ over the statistics of the corresponding fading channel, namely,  \cite{J:Alouini}

\begin{align}  \label{Pd_Average}
\overline{P}_{d} &=  \int_{0}^{\infty} Q_{u}(\sqrt{2 \gamma}, \sqrt{\lambda}) \, p_{\gamma}(\gamma) \,  {\rm d} \gamma  \\
&   = \int_{0}^{\infty} Q_{u}\left(\sqrt{2 \gamma}, \sqrt{2 G^{-1}(u, P_f)}\right) \, p_{\gamma}(\gamma) \,  {\rm d} \gamma.
\end{align}
To this effect,  by substituting  \eqref{Cascaded} in \eqref{Pd_Average} it follows that

\begin{equation}  \label{Pd_Cascaded}
\overline{P}_{d} =  \int_{0}^{\infty} \frac{1}{\gamma } \,  Q_{u}(\sqrt{2 \gamma}, \sqrt{\lambda})  \,   G_{0, N}^{N, 0} \left[ \frac{\gamma}{\overline{\gamma}} \left| ^{  \, \,  \quad \, \, \,   \, \, -     }_{\underbrace{1, 1, \cdots, 1}_{N}} \right.  \right]     {\rm d} \gamma.
\end{equation}
The above expression can be evaluated  using  Theorem $1$ since the involved integral is a special case of \eqref{integral_problem}. Hence, by performing the necessary variable transformation in \eqref{solution} and substituting in \eqref{Pd_Cascaded} yields \eqref{Average_Pd}, which completes  the proof.
\end{proof}

\subsection{Square-Law Selection (SLS)}

Square-law selection is  an effective and relatively simple diversity method \cite{J:Alouini}. Its operation is based on selecting the branch, among $L$ branches, with the maximum decision statistic, $y_{\rm SLS} = \max (y_{1}, \cdots , y_{L})$. For  ED over fading channels, the corresponding average probability of detection  is given by

\begin{equation} \label{diversity}
\overline{P}_{d, {\rm SLS}} \triangleq  1 - \prod_{i = 1}^{L} \{1 - \overline{P}_{d}(\overline{\gamma}_i)\}.
\end{equation}
\begin{corollary}
For $u, \lambda, \overline{\gamma} \in \mathbb{R}^{+}$ and $N \in \mathbb{N}$, the average probability of detection over $N$*Rayleigh  channels with square-law selection is expressed as

\begin{equation} \label{Average_Pd_SLS}
\overline{P}_{d, {\rm SLS}} =  1 - \prod_{i = 1}^{L} \left\lbrace 1 - {\huge  G}_{2,1: 1, 3: 1, N+1}^{0,1: 1, 0: N, 1} \left( ^{\frac{u}{2}, \frac{u-1}{2}}_{\, \, \, \,  \frac{u-1}{2}} \left|^{\quad \frac{1}{2}}_{0, -u, \frac{1}{2}}\right.  \left|  ^{\, \quad  \,  1 }_{1, \cdots , 1, 0, 1} \right| - \frac{\lambda}{2}, - \frac{1}{\overline{\gamma}_{i}}    \right) \right\rbrace .
\end{equation}
\end{corollary}

\begin{proof}
The proof follows by substituting \eqref{Average_Pd} into \eqref{diversity}.
\end{proof}

\begin{figure}[ht]
\centering

\subfigure[]{
   \includegraphics[width =15cm, height = 12cm] {Figure_1.eps}
   \label{fig:subfig1}
 }

 \subfigure[]{
   \includegraphics[width = 15cm, height = 12cm] {Figure_2.eps}
   \label{fig:subfig2}
 }

\label{myfigure1}
\caption{$\overline{P}_d$ vs $\overline{\gamma}$ for different $N$ and $L$ with $u = 5$ and $P_f = 0.1$. }
\end{figure}

\section {Numerical Results}
\label{Results}
The offered results are used in analyzing the behavior and performance of ED based spectrum sensing  over $N$*Rayleigh fading channels for   single-channel and multi-channel cases. This enables us to quantify the corresponding detrimental effects and propose simple and efficient compensation methods.

\begin{figure}[ht]
\centering
   \includegraphics[width =15cm, height =12cm] {Figure_3.eps}
 \label{myfigure1}
\caption{ ROC curve for different $N$ and $L$ with $u = 4$ and $\overline{\gamma} = 12$dB.}
\end{figure}

Fig.  $1$ demonstrates the average probability of detection as a function of the average SNR for     different values of $N$ and $L$ and for  $u = 5$ and $P_{f} = 0.1$, which is considered realistic for most practical applications, such as spectrum sensing.  The  value of $\overline{P}_d$ is shown to reduce  considerably as the number of cascaded channels increases. For example, for $\overline{\gamma} = 15$dB the $\overline{P}_d$ deviation between $N = 1$ and $N=3$ is   $31 \%$ whereas, that between $N=3$ and $N = 5$ for $\overline{\gamma} = 20$dB is $28 \%$.  These cases correspond to deviations that   render the ED capability inadequate since the achieved $\overline{P}_d$ is practically low even at the high SNR regime.   However, it is noticed that employing SLS  provides considerable  performance compensation even for a  small number of diversity branches. Indicatively, it is shown that  when $N=5$, the $\overline{P}_{d}$ increases substantially  for any extra added branch $L$.  This is also illustrated in the receiver operating characteristics (ROC) curve in  Fig. 2, where the value of $\overline{P}_{m}$ for $N = 5$ and $L=3$ is comparable to that for  $N = 1$ and $L=1$. As a result, the detector appears to  perform  better  when   $L\geq 4$, than in the respective single Rayleigh fading scenario. Furthermore,  the overall performance benefits of SLS are more notable in the moderate and low SNR regimes where the single channel scenario performs quite poorly.  \\
\indent
Finally, unlike the single-channel case where increasing $N$ degrades the performance substantially, a slight degradation is observed as $N$ increases  when adopting SLS.    Overall, in  both low and high average SNR values, it is observed that considering in practice a  $3-$branch  SLS receiver can sufficiently overcome the severe  degradation by  cascaded  fading effects.

\section{Conclusion} \label{conc}

This paper quantified the effects of cascaded fading on energy detection.  A generic analytic solution was firstly derived for an integral that involves a product of a Marcum $Q-$function, a Meijer $G-$function and a power term. This solution was subsequently employed in the derivation of closed-form expressions for the average probability of detection over $N$ cascaded Rayleigh fading channels, which was then extended to the case of square-law selection.  It was shown that  the involved number of cascaded channels affect considerably the achieved performance. However, the corresponding  degradation can be effectively compensated with the aid of square-law selection since it was shown that  three or more branches are sufficient for achieving   comparable or better performance than conventional detection over   Rayleigh fading conditions.

\bibliographystyle{IEEEtran}
\thebibliography{99}

\bibitem{J:Alouini}
F. F. Digham, M. S. Alouini, and M. K. Simon,
``On the energy detection of unknown signals over fading channels,"
\emph{IEEE Trans. Commun}. vol. 55, no. 1, pp. 21${-}$24, Jan. 2007.

\bibitem{Paschalis_1}
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\end{document}

redpajama_set_name: RedPajamaArXiv