MMCR fouth-generation upgrade

Description

Since the mid-1990s, MMCR has been the primary radar system used by the ARM Climate Research Facility for fundamental research on the effects of clouds and precipitation on the climate. Through the 2009 American Recovery and Reinvestment Act, the U.S. DOE’s Pacific Northwest National Laboratory recently funded ProSensing Inc. of Amherst, Massachusetts to carry out the fourth-generation upgrade of the five existing MMCR systems. Upgrades to MMCR include a redesigned, wide dynamic range IF section; state-of-the-art PC-based data system; and new processing software. The upgrade will include an embedded arbitrary waveform generator, allowing use of custom pulse compression waveforms with predicted range sidelobe suppression of greater than 60 dB. Simultaneous transmission of a linear FM chirp and short pulse will allow the General Mode to sample both the boundary layer and high-level clouds. The PC-based data acquisition system, using a high performance 16-bit, 120 MS/s digital receiver, has a single-sample dynamic range of approximately 85 dB. Combined with 30:1 or 60:1 pulse compression waveforms, the expected dynamic range of the system is close to 100 dB, potentially eliminating the need for the specialized precipitation mode used in the current MMCR system.