Signals. PSK: Tetra

TETRA

Professional digital trunking system, pi/4 DQPSK

1) Tetra. The record send by ponder_.

2) Another good example of Tetra signal. Send by sergo2007.

Author: SergUA6

Band Width ~ 22000 Hz

Low Range ~ 2000 Hz, shift is possible, acception in SSB

Baud Rate 18000 Hz

n-Ary (PSK/MPSK) PSK-8, pi/4 DQPSK

Carrier frequency ~ 13242 Hz, shift is possible, acception in SSB

ACF ~56-57 and 14 ms

RX mode SSB

Sonograms:

pic.1 Generall view

pic.2 the signal in 4th exponantion

pic.3 the signal in 8th exponantion

Diagrams:

pic.4 manipulation speed

pic.5 Phase constellation

pic.5 ACF after PSK demodulator

TETRA - is the standard called to replace analogue systems of type PMR on VHF range. It was established approximately in 1995. From the point of view of a signal, it is easily enough recognised under the basic characteristics, such are speed of manipulation 18000 Hz and individual ACF. It is necessary to notice that, despite wide enough prevalence, there are almost no good records of this type of signals, because relvatively wideband strips IF and AF bands are required, altought we have two records with this signal, with good quality.