R&S®EFA40/43 Test Receiver (DVB-T)
Comprehensive analysis/demodulation/monitoring of digital terrestrial TV signals
Production testing on modulators and transmitters
EFA's analysis capabilities make it possible to pinpoint problems such as interferers and inadequate carrier suppression: the constellation diagram shows the symbols, but only if a single carrier is affected - the difficulty is localization. This is exactly what the I/Q measurement function does: symbols are displayed as a function of carriers (frequency domain) to locate the problem in the spectrum display. Once the interferer is localized, the constellation display can be used for further evaluation. This approach can also be used with the MER-vs-frequency measurement function.
Transmitter installation and adjustment of single frequency networks (SFN)
The time domain analysis extends EFA's range of applications to SFN installation and adjustment - an area where spectrum and impulse-response analysis are very useful. The impulse response function makes it possible to visualize the delay between two transmitters at a reception point. This measurement function can be used to optimize the delay between the transmitters. The zoom function makes it possible to see fast echoes, for example direct reflections from a building, mountain etc.
Coverage measurements on terrestrial signals (see photo above)
To allow measurements to be performed under even the worst reception conditions, a single keystroke will optimize the OFDM demodulator for mobile reception (where a lot of impairments affect transmission quality) or stationary reception. The algorithms for speed and channel equalization are optimized, as is internal level control.
Monitoring TV transmitters and transposers
EFA is the perfect solution for DVB-T signal monitoring. An alarm is triggered if one of the selected parameters exceeds the threshold that has been set. The incident level, OFDM synchronization, MER (modulation error ratio), BER (before Viterbi and before Reed-Solomon decoders) and the MPEG2 transport stream output can be checked in realtime independent of other measurements and decoding. If an error occurs, a 1000-row register is available to record the date, time and designation of the event. The MPEG2 decoder option EFA-B4 extends monitoring capabilities. Realtime measurements to test specifications for DVB systems (ETR290 - priorities 1, 2 and 3) can be performed and make the EFA a complete DVB-T monitoring system.
