This application example implements an end-to-end baseband communications system compliant to the US MIL_STD_188_110B intended for long-haul and tactical communications.
This model supports four different data rates: 1200bps, 600bps, 300bps and 150bps. It also implements two different interleaver lengths: 0.6s and 4.8s.
The transmitter system consists of a rate 1/2 FEC encoder with constraint length 7, an interleaver matrix as specified by the standard, binary to gray mapping, 8-PSK modulation and finally, data scrambling using a randomizing sequence.
The channel has been model using a combination of blocks from the RF Impairments and Channel models sublibraries of the Communications Blockset such as: AWGN channel, Phase and Frequency offset and I/Q imbalance.
The receiver uses a LMS equalizer to recover the signal before it is sent to the demodulator, channel symbol demapping, deinterleaver and Viterbi algorithm-based decoder.
The system uses extensively blocks from the DSP and Communications Blockset.
Optionally, by means of the Real-Time Workshop (RTW), one can also generate C-code as well as a standalone executable of the whole model. |
