Platform Harvest S-band January 2013

Progress toward the use of S-band SoOp in sea surface remote sensing was demonstrated in a 2012-2013 experiment based at the Harvest Oil Platform located at 34.469° N and 120.682° W, roughly 11 km from Point Conception, Santa Barbara, CA. Satellite transmissions from the XM-radio service were observed, using one channel each from the “Rhythm” (located above 85°W) and the “Blues” (115°W) satellites. Each downlink channel had a bandwidth of 1.886 MHz with a symbol rate of 1.64 Msps in Quadrature Phase Shift Key (QPSK) modulation. Two S-band antennas were deployed at approximately 27 m over the ocean surface. A LHCP antenna (Terk XM6) was pointed towards the satellite to receive the direct signal, while a RHCP antenna (Antcom 3M23R-A-XT2) was oriented towards the sea surface to receive the reflected signals. Following low noise amplifiers for both the direct and reflected antennas, a Universal Software Radio Peripheral 1 (USRP1) was then used to digitize, down-convert, and sample the measurements at an 4 MHz I/Q sample rate using 8-bit complex quantization. S-band data was recorded in two-minute blocks every two hours between September 25, 2012 and May 23, 2013. This dataset is the complex cross- and auto- correlations for the separated XM3 and XM4 channels, processed at a 4-ms coherent sampling time.