Pulse or digital communications – Repeaters – Testing
Patent
1992-09-02
1994-11-08
Chin, Stephen
Pulse or digital communications
Repeaters
Testing
375 58, 455 63, H04B 1404
Patent
active
053634071
ABSTRACT:
A method of configuring an optimum communication system for communicating on adjacent frequency bands with minimal interference between adjacent channels comprises serially coupling a selected encoder to a mapper, a transmit filter, a low pass filter and a modulator, and constructing a receiver with a seriallycoupled receive filter and decoder. The transmit filter is optimized by choosing transmit filter coefficients d.sub.opt which maximize the inband to adjacent-band power. Transmitter coefficients d.sub.opt are obtained by solving an eigenvalue problem which takes into account the power spectrum of the encoder, mapper and receive filter. The optimum transmitter coefficients are then employed in the transmitter to shape the transmitted signal, increasing the adjacent channel interference protection ratio (ACIPR). In an alternative embodiment, further constraints are placed upon the system, such as reducing the combined impulse response of the transmit filter, low pass filter and the receive filter to zero at the beginning of subsequent symbol periods. The resulting system then exhibits an increased ACIPR along with a reduced intersymbol interference.
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Chennakeshu Sandeep
Ramesh Rajaram
Chin Stephen
General Electric Company
Snyder Marvin
Tse Young
Zale Lawrence P.
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