Title:
POST PROCESSING OF SPREADING CODES IN A MOBILE TELECOMMUNICATIONS SYSTEM
Document Type and Number:
WIPO Patent Application WO2001065715
Kind Code:
A3
Abstract:
In mobile telecommunications systems, such as UMTS, user communications can be transmitted in parallel within a single timeslot by spreading the different user communications amongst a plurality of orthogonal spreading codes. Each spreading code has a characteristic spreading factor. The communications transmitted in each timeslot are joint detected and de-spread into the original user communications by a joint detection algorithm. There is provided a method of post-processing the results of the joint detection algorithm when the spreading factors are unknown. The method of post-processing operates without the need to apply the joint detection algorithm more than once. Consequently, spreading codes with different spreading factors can be used in one timeslot.
Inventors:
JOHNSON DAVID (GB)
Application Number:
PCT/GB2001/000846
Publication Date:
December 27, 2001
Filing Date:
February 28, 2001
Export Citation:
Assignee:
ROKE MANOR RESEARCH (GB)
JOHNSON DAVID (GB)
JOHNSON DAVID (GB)
International Classes:
H04B1/707; H04J13/00; H04J11/00; (IPC1-7): H04B1/707
Foreign References:
| US5978428A | 1999-11-02 |
Other References:
MAYER J ET AL: "Realtime feasibility of joint detection CDMA", EPMCC. EUROPEAN PERSONAL MOBILE COMMUNICATIONS CONFERENCE TOGETHER WITH ITG-FACHTAGUNG, MOBILE KOMMUNIKATION, XX, XX, no. 145, 1997, pages 245 - 252, XP002112135
GE H ET AL: "MULTI-RATE LMMSE DETECTORS FOR ASYNCHRONOUS MULTI-RATE CDMA SYSTEMS", ICC '98. 1998 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS. CONFERENCE RECORD. NEW CENTURY COMMUNICATIONS. ATLANTA, GA, JUNE 7 - 11, 1998, IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS, NEW YORK, NY: IEEE, US, vol. 2 CONF. 5, 7 June 1998 (1998-06-07), pages 714 - 718, XP000890966, ISBN: 0-7803-4789-7
GE H ET AL: "MULTI-RATE LMMSE DETECTORS FOR ASYNCHRONOUS MULTI-RATE CDMA SYSTEMS", ICC '98. 1998 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS. CONFERENCE RECORD. NEW CENTURY COMMUNICATIONS. ATLANTA, GA, JUNE 7 - 11, 1998, IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS, NEW YORK, NY: IEEE, US, vol. 2 CONF. 5, 7 June 1998 (1998-06-07), pages 714 - 718, XP000890966, ISBN: 0-7803-4789-7
Download PDF:
Previous Patent: IRR FILTER FOR A CDMA RECEIVER
Next Patent: CORRECTION OF RECEIVED SIGNAL AND INTERFERENCE ESTIMATES
Next Patent: CORRECTION OF RECEIVED SIGNAL AND INTERFERENCE ESTIMATES