PURPOSE: To increase the number of permitted speeches by reducing it that plural transmission data from the same transmitter are interfered with each other at correlation detection by a receiver.
CONSTITUTION: A 0-th element signal, a 1st element signal and a 2nd element signal from a Walsh function 0-th generator 105, a Walsh function 1st generator 106, and a Walsh function 2nd generator 107 are multiplexed by a spread code from a spread code generator 101 by multipliers 108, 110, 112 and the products are used for spread codes of a synchronizing signal, speech data and a call control signal respectively. Then the synchronizing signal, the speech data and the call control signal sent from a synchronizing signal generator 102, a speech data source 103, and a call control signal processing unit 104, respectively are subject to spread operation by multipliers 109, 110, 111, the results are added by an adder 114 to generate base band data, and a carrier frequency modulator 115 modulates the generated data into data for a radio frequency band. A receiver conducts the operation symmetrical to above.
SEKINE KIYOKI (JP)
SATO TAKURO (JP)
FUKAZAWA ATSUSHI (JP)
