Multi-user communication of voice and data

Details Multi-user communication of voice and data Multi-user communication of voice and data

2000-09-15

2004-03-23

Patel, Ajit (Department: 2664)

Multiplex communications

Communication over free space

Having a plurality of contiguous regions served by...

C370S337000, C370S342000, C370S347000

Reexamination Certificate

active

06711144

ABSTRACT:

This invention relates to multi-user communication of voice and data.
BACKGROUND
In wireless cellular communications, a large geographic area is divided into cells, each served by a single base station communicating with multiple users in its cell.
3GPP2, a standards organization developing 3rd-generation wireless communication standards, is developing a new wireless air interface standard called 1xEV-DO, described in Baseline Text for the 1xEV-DO Physical Layer: -2000821-021-1xEV_Phy_Layer_Spec_v21, and Baseline Text for the 1xEV-DO Upper Layers (excluding Physical Layer): C30-20000821-021-114b Editor, 1xEV-DO-Sig.baseline_v55_clean, both available from 3GPP2
This standard supports high-speed data communications between MS's and their BS (acronyms used in this discussion are defined below) at bit rates of up to 2.457 Mbit/s in the forward link (from BS to MS's) using only 1.25 MHz of spectrum. However, 1xEV-DO cannot efficiently support delay-sensitive, low-rate traffic, such as voice. One can carry voice packets in a 1xEV-DO system using VoIP, however, such an approach wastes significant amounts of bandwidth since the physical layer packet size of 1xEV-DO is much bigger than the size of VoIP packets.
For convenience, the following acronyms used here have the indicated meanings.
1xEV-DO
1xEV-Data Only
1xEV-DV
1xEV-Data and Voice
3GPP2
3rd Generation Partnership Project 2
BS
Base Station
CDMA
Code Division Multiple Access
CRC
Cyclic Redundancy Checksum
IS-95
TIA/EIA Interim Standard 95
MS
Mobile Station
SIR
Signal to Interference Ratio
TDMA
Time Division Multiple Access
VoIP
Voice over Internet Protocol
SUMMARY
In general, in one aspect, the invention features a method that includes sending data in some time slots of a forward link from a base station to at least one remote station in a wireless communication system, and sending voice information from the base station to the at least one remote station in some other time slots of the forward link, the data being sent in a time division multiple access (TDMA) mode, the voice information being sent in a code division multiple access (CDMA) mode.
Implementations of the invention may include one or more of the following features. The data and voice information may be sent in a manner that is compatible with a remote station that is receiving data from the base station according to the 1xEV-DO standard. The CDMA mode may include assigning more than one Walsh code to a single voice call. The time slots in which voice information is sent may be chosen so that at least every fourth slot is not used for voice information and is available for sending the data. The voice information may be sent to different remote stations. The time slots may be used only as needed for sending voice information. The codes assigned to different remote stations may be allocated different power levels for the voice information. Each code used in a voice time slot may be allocated only enough power to achieve a predetermined voice quality.
Other advantages and features will become apparent from the following description and from the claims.


REFERENCES:
patent: 5805581 (1998-09-01), Uchida et al.
patent: 6249683 (2001-06-01), Lundby et al.
patent: 6320873 (2001-11-01), Nevo et al.
patent: 6526036 (2003-02-01), Uchida et al.
patent: 0 932 267 (1999-07-01), None
patent: 00 54437 (2000-09-01), None
patent: 01 86837 (2001-11-01), None
cdma2000 High Rate Packet Data Air Interface Specification; 3GPP2 C.S0024; Version 4.0; Oct. 25, 2002; 3rdGeneration Partnership Project Z “3GPPZ”.
Viterbi, A.J., “CDMA Principles of Spread Spectrum Communication”, Addison-Wesley Wireless Communications, (1995).
Prasad R. et al, “Hybrid TDMA/CDMA Multiple Access Protocol for Multi-Media Communications”, IEEE International Conference on Personal Wireless Communications Proceedings, Feb. 19, 1996, pp. 123-128.

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