摘要 |
PCT No. PCT/US84/01315 Sec. 371 Date Aug. 14, 1984 Sec. 102(e) Date Aug. 14, 1984 PCT Filed Aug. 14, 1984 PCT Pub. No. WO85/00903 PCT Pub. Date Feb. 28, 1985.An analog signal stacking method and apparatus permits transmission of n analog signals of given spectrum width over a narrow band communication circuit having bandwidth approximately equal to the spectrum width of one analog signal by compressing the spectrum of each signal by a factor of 1/n and frequency offsetting the compressed signals to occupy contiguous frequency bands within the bandwidth of the circuit. Received signals are processed to remove the frequency offset and expand the baseband signals to restore each analog signal to its normal spectrum. A dial through circuit permits application of the stacking feature to place two conventional dialed calls on a single line of the telephone network using a circuit for processing both dial and voice signals.
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