Mobile X-band dual polarization phased-array radar: System requirements and development
UMX2P utilizes 64 solid state T/R modules and a phase-tilt antenna developed at the Center for Collaborative Adaptive Sensing of the Atmosphere (CASA). The T/R module uses a Common Leg architecture, which enables sharing of digital attenuator, phase shifter and gain block between transmit and receive channels. In order to maximize output power and reduce insertion loss a simultaneous transmit and receive of polarizations is not supported. However, signal processing methods exist in order to retrieve simultaneous transmit/receive polarimetric parameters from alternating transmit/receive schemes. The radar's antenna is based on a series-fed array of dual-polarized aperture coupled patch antennas, which enables electronic azimuth scanning and mechanical elevation scanning. Owing to low peak radiated power, it is crucial that the average transmitted power is increased by means of pulse compression technique, which employs nonlinear frequency modulated (NLFM) waveform and a dedicated inverse filter. The developed 2 channel up/down converter combined with a digital transceiver allows mitigation of blind range zone at no reduction in pulse repetition frequency. It also enables a frequency hopping operation in order to increase number of independent samples. This paper documents the high-level system architecture and the current state of development.