what counntries do space surveillance ethnocentric usian that i am i ve assumed that we and the xussr were the only countries with significant capabilities to track non cooperative objects in low earth orbit grazing in a couple of databases recently i found that japan has some optical capabilities along this line and also uses a radar designed for other purposes for orbital debris surveys it isn t clear whether the radar can determine orbital elements for the objects it detects abstracts of the articles are appended this leads to the more general question do yet other people than the us russia and japan do space surveillance and if so how and why allen thomson saic mclean va usa abstracts optical tracking of the experimental geodetic satellite egs takabe masao itabe toshikazu aruga tadashi radio research laboratory review issn x vol march p in japanese with abstract in english this paper reports the optical tracking results of egs experimental geodetic satellite which was launched on august by nasda the egs optical tracking experiment process and an outline of the radio research laboratory rrl optical ground station are discussed a star tracking technique for optical equipment calibration and satellite tracking technique for orbit prediction improvement are also described the accuracy of egs tracking data obtained by rrl at the request of nasda is also discussed in addition it is briefly demonstrated that the position of the japanese amateur satellite jas which was launched with the egs was accurately determined by means of a satellite tracking video it is clear from this experiment that optical observation data i e satellite direction data are very useful for satellite orbit determination during initial launch stages furthermore the results confirm the effectivenes of these two satellite optical tracking techniques mu radar measurements of orbital debris sato toru kayama hidetoshi furusawa akira kimura iwane kyoto university japan aiaa nasa and dod orbital debris conference technical issues and future directions baltimore md apr p rpn aiaa paper distributions of orbital debris versus height and scattering cross section are determined from a series of observations made with a high power vhf doppler radar mu radar of japan an automated data processing algorithm has been developed to discriminate echoes of orbiting objects from those of undesired signals such as meteor trail echoes or lightning atmospherics although the results are preliminary they showed good agreement with those from norad tracking radar observations using a much higher frequency it is found that the collision frequency of a space station of km x km size at an altitude of km with orbiting debris is expected to be as high as once per two years monitoring of the mu radar antenna pattern by satellite ohzora exos c sato t inooka y fukao s kyoto univ japan kato s kyoto univ uji japan radio atmospheric science center in international council of scientific unions middle atmosphere program handbook for map vol p publication date jun as the first attempt among mst mesosphere stratosphere troposphere type radars the mu middle and upper atmosphere radar features an active phased array system unlike the conventional large vhf radars in which output power of a large vacuum tube is distributed to individual antenna elements each of solid state power amplifier feeds each antenna element this system configuration enables very fast beam steering as well as various flexible operations by dividing the antenna into independent subarrays because phase shift and signal division combination are performed at a low signal level using electronic devices under control of a computer network the antenna beam can be switched within microsec to any direction within the zenith angle of deg since a precise phase alignment of each element is crucial to realize the excellent performance of this system careful calibration of the output phase of each power amplifier and antenna element was carried out among various aircraft which may be used for this purpose artificial satellites have an advantage of being able to make a long term monitoring with the same system an antenna pattern monitoring system for the mu radar was developed using the scientific satellite ohzora exos c a receiver named mum mu radar antenna monitor on board the satellite measures a cw signal of to watts transmitted from the mu radar the principle of the measurement and results are discussed equatorial radar system fukao shoichiro tsuda toshitaka sato toru kato susumu kyoto university uji japan cospar iaga scostep et al plenary meeting th workshops and symposium on the earth s middle atmosphere espoo finland july advances in space research issn vol no p a large clear air radar with the sensitivity of an incoherent scatter radar for observing the whole equatorial atmosphere up to km altitude is now being designed in japan the radar will be built in pontianak west kalimantan indonesia deg n deg e the system is a mhz monostatic doppler radar with an active phased array configuration similar to that of the mu radar in japan which has been in successful operation since it will have a pa product of about x to the th w sq m p average transmitter power a effective antenna aperture with a sensitivity of approximately times that of the mu radar this system configuration enables pulse to pulse beam steering within deg from the zenith as is the case of the mu radar a variety of operations will be made feasible under the supervision of the radar controller a brief description of the system configuration is presented
