Experimental results concerning the influence of wave propagation on telemetry data transmission at 230 MHz compared with 2.3 GHz

The data transmission in the VHF and UHF band from surface vehicles to a fixed receiving station was studied by experiments in different kinds of terrain. In broadband systems, as used for telemetry, it was necessary to compare not only the received signal power, but also to add another criteria for the transmission quality, e.g. the bit error rate in digital systems. Thus a digital pulse code modulated data stream was simultaneously transmitted in both bands. The signal strength and the missed frame synchronization words of both data links were recorded on paper tapes for a quick look analysis. A magnetic type was produced for a computer comparison of each piece of information (bit) with the known transmitted bitpattern. The bit error rate per data frame of both systems was then correlated.