Multiplex communications – Wide area network – Packet switching
Patent
1987-12-04
1989-10-10
Olms, Douglas W.
Multiplex communications
Wide area network
Packet switching
3701001, 3701041, 375 15, 375 57, 375101, H04J 316, H04B 110
Patent
active
048736830
ABSTRACT:
A time division multiple access (TDMA) radio system conveying a quadrature phase shift keying (QPSK) modulated data signal is disclosed. In order to overcome multipath distortion and phase variation introduced by the radio channel, a synchronizing poriton of a TDMA timeslot is transmitted in only one vector of the QPSK modulation. The system utilizes the one vector synchronizing portion to develop a channel profile estimate which is applied to the received message portion of the QPSK data signal to compensate for the multipath distortion and phase variation during one TDMA timeslot.
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Borth David E.
Labedz Gerald P.
Rabe Duane C.
Wang Chih-Fei
Chin Wellington
Hackbart Rolland R.
Jenski Raymond A.
Motorola Inc.
Olms Douglas W.
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