Signal processing of Beam-multiplexed data for Phased-Array weather radar

The S-band Phased Array Radar(PAR) has been recently installed at the National Weather Radar Testbed (NWRT) in Norman, Oklahoma. It is equipped with the SPY-1A phased array antenna loaned by the NAVY and can rapidly and adaptively scan multiple regions of interest. Beam-multiplexing makes further use of the PAR's beam agility to provide high-quality and rapid-update weather observations. In a beam-multiplexing mode regions of interest are re-sampled after weather signals become uncorrelated. As a result, the statistical error of spectral moment estimation can be reduced optimally through the average of a number of independent measurements. Moreover, PAR can be tasked to probe other regions during the period of re-sampling to maximize the use of radar resources. Thus PAR can provide fast update of weather information in regions of interest. In this work, the idea of beam-multiplexing is presented and verified using numerical simulation. An experiment was designed to demonstrate the feasibility and advantage of beam-multiplexing. The PAR and the research WSR-88D (KOUN) were coordinated to simultaneously scan the same region using beam-multiplexing and conventional sampling, respectively. Preliminary results have shown that data quality and update rate can be improved using PAR beam-multiplexing.