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Title: QAM multi-path characterization due to ocean scattering

Conference ·
OSTI ID:976394

A series of RF channel flight characterization tests are to be run, in early March, to benchmark high speed, 16QAM multi-path performance over the ocean surface. The modulation format being tested is a 16 differential phase, absolute amplitude, two level polar quadrature amplitude modulation. The bit rate is 100 Megabits per second. This transmitted signal will be generated in a burst mode, being on for 40 microseconds once every 40 milliseconds. An aircraft will radiate the RF test signal at 5 different altitudes. The aircraft will make two inward flights at each altitude with vertical and horizontal polarization respectively. Receivers are to be placed in two different locations using circular antenna polarization. One receiver will be placed at an altitude of 230 feet above the ocean surface, and the other on a boat with the antenna placed just up off of the ocean surface. Data is to be collected over multiple wavelength changes in the difference between the line of sight and the reflected multi-path ray. The real time signal strength variation is to be recorded as well. Analysis of the resulting data will show flat fading and frequency selective fading effects. The test is run over two different days to provide for some variation in sea state conditions. This resulting information will help quantify the effectiveness of this novel modulation scheme for missile telemetry end event data applications.

Research Organization:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Organization:
USDOE
OSTI ID:
976394
Report Number(s):
LA-UR-02-6522; TRN: US201018%%1216
Resource Relation:
Conference: Submitted to: International Telemetering Conference, San Diego, CA, Oct. 21-24, 2002
Country of Publication:
United States
Language:
English