Performance Enhancement of a Multichannel Uncoordinated Code Hopping DSSS Signaling Scheme Using Multipath Fading Compensator

In this paper, a multipath fading compensator(MFC) has been introduced and demonstrated to reduce the signal distortion which arose due to Doppler effect, multipath propagation and self-interference for a multichannel uncoordinated code hopping direct sequence spread spectrum (UCH-DSSS) signaling in underwater communication. The bit error rate (BER) performance analysis of the proposed system obtained both analytically and using P-Spice circuit simulation model with and without jamming signal is presented. It is observed that the BER is independent of the frequencies (used in focused acoustic field (FAF) experiments FAF-06 and FAF-05) and is also less than those of the previous works. Oscilloscope traces indicate that the experimental waveform of the proposed four-channel UCH-DSSS transceiver is almost close to those obtained using P-Spice circuit simulation. The experimental values of BER measured by BER meter also matched well with the BER obtained theoretically. Noise margin and distortion performance also are analyzed from the eye pattern which shows that noise margin and distortion also are independent of frequencies ( used in both FAF-06 and FAF-05) and the bandwidth of operation of FAF-06 is similar to 5.5 times more than that of FAF-05.