Detection of digital signals received from multipath channels

Details Detection of digital signals received from multipath channels Detection of digital signals received from multipath channels

1989-01-23

1991-04-02

Olms, Douglas W.

Pulse or digital communications

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Direct sequence

455143, 364726, H04L 100

Patent

active

050051890

ABSTRACT:
Methods for detection or, or equivalently, demodulation of phase-and-amplitude-shift-keyed communication signals that may be received via multipath propagation or dispersion in a noisy channel are disclosed. The signal format has a block structure with a fixed pattern preceding and following the data portion of each block. Implementation is accomplished in real-time by obtaining samples of the complex-envelope of the received waveform, processing at the symbol rate mainly in the frequency domain, then returning to the time domain with a coagulated signal where ordinary detection of the symbols is completed according to the modulation in use. The signal format and computation in the frequency domain permit the estimation of the multipath-structure of the channel, which in turn permits the estimation of the data using a reasonable amount of processing. Performance of the basic method is substantially improved by generating a metric and searching for alterations of the data that reduce the metric. The search can be controlled by an indicant vector that identifies those symbols of a block that are likely to be in error. Synchronization is obtained by trial using the basic method to compare the detected pattern with the known pattern.

REFERENCES:
patent: 3984634 (1976-10-01), Painter
patent: 4063281 (1977-12-01), Kornreich et al.
patent: 4412339 (1983-10-01), Alfke et al.
patent: 4529941 (1985-07-01), Lipoff
patent: 4564952 (1986-01-01), Karabinis et al.
patent: 4780885 (1988-10-01), Paul et al.

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