| 摘要 |
<p>A demodulator used in a base band processor of the spread spectrum radio transceiver includes a demodulator circuit for spread spectrum phase shift keying (PSK) demodulating an information signal received from a radio circuit. The information signal includes data symbols formed from a plurality of high rate mode chips forming a spread spectrum information signal. At least one predetermined code function correlator is in line with a signal input for decoding the information signal according to a predetermined code. A carrier loop circuit allows phase and frequency tracking of the information signal and a chip decision circuit is operative with the carrier loop circuit for tracking high rate mode chips. A decision feedback equalizer formed from a feedback finite impulse response filter is operative with the chip decision circuit and the carrier loop circuit. It has a plurality of feedback taps. At least one feedback tap is selected for logical add/subtract operations to aid in canceling multipath signal echoes. A feed forward finite impulse response filter can also be positioned in line to the code function correlator and the signal input and has a plurality of feed forward taps that are selected for logical multiply operations to aid in reducing multipath signal echoes. A method aspect of the invention is also disclosed.</p> |
