EP 0765545 A2 19970402 - COMMUNICATIONS SYSTEM AND TRANSMITTING MEANS THEREFOR
Title (en)
COMMUNICATIONS SYSTEM AND TRANSMITTING MEANS THEREFOR
Title (de)
KOMMUNIKATIONSSYSTEM UND ÜBERTRAGUNGSVORRICHTUNG HIERZU
Title (fr)
SYSTEME DE COMMUNICATIONS ET SES MOYENS DE TRANSMISSIONS
Publication
Application
Priority
- GB 9507449 A 19950411
- IB 9600183 W 19960308
Abstract (en)
[origin: WO9632784A2] A spread spectrum communications system comprises a transmitter (40-50) and a receiver (52-64). The transmitter includes mixing means (42) having a first input for connection to a data source (40) and a second input for connection to means (44, 46) for providing a dc free encoded spreading sequence. The output from the mixing means (42) is applied to a pulse shaping filter (48), the output of which controls the frequency of a voltage controlled oscillator (50). The signal which is received at the receiver is applied to a frequency down converter (52) which produces quadrature related signals (I, Q) which are applied to first inputs of mixers (56, 58). A dc free encoded spreading sequence is provided by a spreading sequence source (60) and encoder (62) and is applied to second inputs of the mixers (56, 58); the applied encoded spreading sequence corresponds to that applied to the mixing means (42) in the transmitter. The despread outputs from the mixers (56, 58) are applied to a symbol estimator (64) which recovers the received data. Optionally, a plurality of dc free encoded spreading sequences may be stored in a ROM, and by applying an appropriate address signal to the ROM, a predetermined dc free encoded spreading sequence is applied to the filter (48).
IPC 1-7
IPC 8 full level
H04B 1/707 (2011.01); H04L 27/00 (2006.01)
CPC (source: EP KR)
H04B 1/707 (2013.01 - EP KR)
Citation (search report)
See references of WO 9632784A2
Designated contracting state (EPC)
DE FR GB
DOCDB simple family (publication)
WO 9632784 A2 19961017; WO 9632784 A3 19970103; EP 0765545 A2 19970402; GB 9507449 D0 19950531; JP H10501950 A 19980217; KR 970704274 A 19970809
DOCDB simple family (application)
IB 9600183 W 19960308; EP 96903167 A 19960308; GB 9507449 A 19950411; JP 53083596 A 19960308; KR 19960707037 A 19961210