LINEWIDTH REQUIREMENTS FOR AN OPTICAL MSK HETERODYNE SYNCHRONOUS RECEIVER

The laser linewidth requirements for an optical MSK heterodyne / synchronous receiver is presented taking into account the effect of imperfect phase references. The performance of the receiver is evaluated in terms of the bit-error-rate, receiver sensitivity, and loop bandwidth. It is shown that an IF linewidth of less than 3.0 x 10(-4) of the bit rate is required to avoid the power penalty of 0.5 dB with the rms phase error of 0.11 radians. In comparison, the synchronous PSK, differential MSK, and DPSK heterodyne receivers are more tolerant to the laser phase noise than the synchronous MSK heterodyne receiver.