[PEM15-P01] Study on adaptive clutter rejection system using external receiving antennas for the MU radar
Keywords:Atmospheric radar, Clutter rejection, NC-DCMP method, MU radar
Four turnstile antennas are installed in the MU radar site. The signal from the antenna is sent to the MU radar observation room through the coaxial cable after amplified by the LNA with the limiter and BPF. It is further amplified by the LNA in the observation room, and then down-converted to intermediate frequency (5 MHz) signal to input to the multi-channel receiving system of the MU radar.
We compared the NC-DCMP method using the each received data of 25 channels, which is a conventional clutter suppression method, and the NC-DCMP method using the simple combination of 25 channels and 4 channels of external antennas. In the former case, the S/N of the atmospheric echoes is somewhat degraded, but in the latter case the main lobe shape is guaranteed by 25 channel simple synthesis, so the S/N degradation is not observed. In the latter case, the clutter suppression is sometimes insufficient. This cause is considered to be that the current positions of external antennas are biased to the north side. Antenna positions should be optimized in the future.
We can apply the achievement of this study to the Equatorial MU radar (EMU), which is proposed to be constructed at West Sumatera, Indonesia. The EMU system is the similar as the MU radar, but its antenna consists of 1045 Yagi antennas with 55 groups and it has 64 receiver channels.