초록 ▼

An adaptive interference cancelling system for multibit spread spectrum noise codes wherein a plurality of users in a mobile subscriber access system each operates with a different noise code. Each user receives a composite signal which includes a desired noise coded signal from another user plus an

An adaptive interference cancelling system for multibit spread spectrum noise codes wherein a plurality of users in a mobile subscriber access system each operates with a different noise code. Each user receives a composite signal which includes a desired noise coded signal from another user plus any unwanted interference noise coded signals from other like users in relatively close proximity. The RF demodulator or front end section of each user receiver is coupled to a bank of matched filters which selectively detect and identify any interfering codes. These interfering codes are then regenerated devoid of the desired signal to provide a coherent replica of the interference signal. The received composite signal and the coherent replica of one or more interference signals are applied to individual signal subtractor circuits which operate to cancel the interfering noise coded signals leaving the desired signal to be subsequently matched filter detected free of interference from other users.

대표청구항 ▼

A non-orthogonal code division multiple access communications system for a plurality of users, comprising: a plurality of user communications apparatus, one for each user; each said user apparatus including means for generating and transmitting a mutually different noise coded signal to another said

A non-orthogonal code division multiple access communications system for a plurality of users, comprising: a plurality of user communications apparatus, one for each user; each said user apparatus including means for generating and transmitting a mutually different noise coded signal to another said user apparatus; each said user apparatus further including, means for receiving a composite noise coded signal including a desired noise coded signal transmitted from a predetermined said user apparatus and any undesired interfering noise coded signal transmitted from at least one other said user apparatus, a plurality of noise code selective circuit means in separate signal paths for detecting said interfering noise coded signal included in said composite signal, respective circuit means coupled to said plurality of noise code selective circuit means for regenerating a replica of said interfering noise coded signal detected devoid of said desired noise coded signal, signal combiner means coupled to said composite signal received and said replica signals and being responsive thereto to operably cancel, by the process of subtraction, said interfering signal from said composite signal and leaving said desired signal, and detector means coupled to said signal combiner means for detecting said desired signal free of undesired interference.