1. Field of Invention
The present invention relates to wireless communication. More particularly, the invention is related to an improved system for bit error rate (BER) and packet error rate (PER) testing of wireless short-range communications between two devices.
2. Description of Prior Art
A wireless communication device (WCD) may communicate over a multitude of networks. Cellular networks facilitate WCD communications over large geographic areas. For example, the Global System for Mobile Telecommunications (GSM) is a widely employed cellular network that communicates in the 900 MHZ-1.8 GHZ band in Europe and at 1.9 GHZ in the United States. This system provides a multitude of features including audio (voice), video and textual data communication. For example, the transmission of textual data may be achieved via the Short Messaging Service (SMS). SMS allows a WCD to transmit and receive text messages of up to 160 characters. It also provides data transfer to packet networks, ISDN and POTS users at 9.6 Kbps. While cellular networks like GSM provide a global means for transmitting and receiving data, due to cost, traffic and legislative concerns, a cellular network may not be appropriate for all data applications.
Bluetooth™ is a short-range wireless network technology quickly gaining acceptance in the marketplace. A Bluetooth™ enabled WCD may transmit and receive data at a rate of 720 Kbps within a range of 10 meters, and may transmit up to 100 meters with additional power boosting. A user does not manually instigate a Bluetooth™ wireless network. A plurality of devices within operating range of each other will automatically form a network group called a “piconet”. Any device may promote itself to the master of the piconet, allowing it to control data exchanges with up to seven “active” slaves and 255 “parked” slaves. Active slaves exchange data based on the clock timing of the master. Parked slaves monitor a beacon signal in order to stay synchronized with the master, and wait for an active slot to become available. These devices continually switch between various active communication and power saving modes in order to transmit data to other members of the piconet.
More recently, manufacturers have began to incorporate various devices for providing enhanced functionality in a WCD (e.g., hardware components and software for performing close-proximity wireless information exchanges). Sensors and/or scanners may be used to read visual or electronic information into a device. A transaction may involve a user holding their WCD in proximity to a target, aiming their WCD at an object (e.g., to take a picture), sweeping the device over a tag or document, etc. Machine-readable technologies such as radio frequency identification (RFID), Infra-red (IR) communication, optical character recognition (OCR) and various other types of visual, electronic and magnetic scanning are used to quickly input desired information into the WCD without the need for manual entry by a user.
Short-range communication strategies are ideal for entities seeking to deliver data to information consumers in a certain geographic area. These systems operate mostly in unregulated bands, and may be a cost-effective solution for the generalized dissemination of information. In the case of Radio Frequency communications, the Near Field Communication protocol (NFC IP-1), which received approval under standard ISO/IEC IS 18092 in 2003, uses the 13.56-MHz wavelength, and is composed of a physical layer and data link layer. When devices with an NFC IP-1 compatible chip are brought within 10 centimeters, they can recognize each other and exchange information. This highly intuitive method for communication contrasts previous methods where devices have to be identified by icons on computer screens or selected within Bluetooth networks or WLANs.
While these beneficial characteristics make NFC IP-1 communications ideal for many applications, the actual usefulness of radio frequency communication methods may be limited by the reliability of the wireless connection. Devices must be able to quickly establish a stable communication link, even over a maximum permitted distance, in order to obtain the desired information. Otherwise, the resources applied to provide this information are wasted.
One way to verify the quality of short-range communications is through testing. Current methods require test equipment in controlled conditions in order to determine communication quality. A WCD to be analyzed, also called a unit under test (UUT), may be evaluated by sending NFC IP-1 frames or packets from a test or reference system to the device. The UUT in turn relays the received information back to the test system (loopback). The test system may then check the information to determine positions containing flipped bits (e.g., a “1” that should have been a “0” and vice versa). The tally of these incorrect bits is used to derive a bit error rate (BER) that may be used to evaluate the performance of the UUT. For NFC IP-1 and RFID systems, the system performance is only defined in the connection to the reference antenna that is defined. Therefore, due to different antenna size or shapes of the two connecting items, the near end and far end transmissions are best considered as two independent connections that, as a result, have different performances.
The current testing methods, while effective to evaluate overall connection quality, are not well equipped to help a user pinpoint the source of an error. There is also no standardization for these tests, requiring a custom set-up according to the circumstances of each particular test. Finally, special equipment and software (e.g., a test program used to send test packets) may not be readily available to all users who desire to debug a device (e.g., a field technician). Currently, providing these test resources for all WCD users may be prohibitive due to the additional resource overhead required in the device. This additional space for equipment and/or software may require substantial redesign and cost escalation for the device.
What is needed, and not found within the prior art, is a simplified method to test wireless communication devices so that error statistics may be derived that help define the source of an error. The requirements for the testing (hardware and software) should be standardized so that the test may be run between a multitude of different devices. Finally, the software required for the test should be both flexible and compact so that devices of different capabilities can run different tests in order to determine whether short-range communication resources are operating within specification.