| 摘要 |
<p>An underwater acoustic communications system utilizes phase coherent modulation (56) and demodulation (68) in which high data rates are achieved through the use of rapid Doppler removal, a specialized sample timing control technique and decision feedback equalization including feedforward (76) and feedback equalizers (88). The combined use of these techniques dramatically increases data rates by one and sometimes two orders of magnitude over traditional FSK systems by successfully combating fading and multipath problems associated with a rapidly changing underwater acoustic channel that produce intersymbol interference and make timing optimization for the sampling of incoming data impossible.</p> |
