초록 ▼

The present invention describes a communications system that utilizes frequency division multiple access (FDMA), code division multiple access (CDMA), and time division multiple access (TDMA) techniques for providing efficient use of frequency spectrum while supporting a large number of transmitters

The present invention describes a communications system that utilizes frequency division multiple access (FDMA), code division multiple access (CDMA), and time division multiple access (TDMA) techniques for providing efficient use of frequency spectrum while supporting a large number of transmitters/users (2-6). Many users of the communications system share a common frequency band, but each transmit their respective message bursts (50) at different and specific times via a TDMA technique. To facilitate synchronization of the TDMA technique, each transmitter of the system is synchronized to a common timing reference (1) thereby abating the need to maintain synchronization between the transmitters (2-6) and receivers (8-12) of the system. Each TDMA message is then transmitted via a spread spectrum technique by multiplying (82) the message burst to be transmitted by a pseudo-random sequence of ones and zeroes (84) and transmitting such spread spectrum message burst for reception by one or more receivers within the system.

대표청구항 ▼

[ We claim:] [1.] A communications system utilizing time division multiple access (TDMA) and code division multiple access (CDMA) techniques for efficiently transmitting bursts of data from a plurality of users at different data rates to one or more receivers within the system, comprising:a timing r

[ We claim:] [1.] A communications system utilizing time division multiple access (TDMA) and code division multiple access (CDMA) techniques for efficiently transmitting bursts of data from a plurality of users at different data rates to one or more receivers within the system, comprising:a timing reference for generating a precise timing signal and a corresponding precise time reference;a plurality of transmitters, coupled to the timing reference for providing synchronization between the plurality of transmitters, for transmitting the bursts of data at precise times and time intervals and at a predetermined frequency within a TDMA superframe wherein synchronization between said plurality of transmitters and the one or more receivers is not needed; andwherein the bursts of data is modulated with a carrier and is multiplied with a spreading sequence thereby permitting more than one of the plurality of transmitters to transmit at a same time and at the predetermined frequency.