SYSTEM AND METHOD FOR MAINTAINING WIRELESS CHANNELS OVER A REVERSE LINK OF A CDMA WIRELESS COMMUNICATION SYSTEM

• US 20100208708A1
• Filed: 04/27/2010
• Published: 08/19/2010
• Est. Priority Date: 06/01/1998
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Tantivy Communications Incorporated (InterDigital, Inc.)
• Inventors: Proctor, James A. JR.
• Granted Patent: US 8,139,546 B2
• Time in Patent Office: Days
• US Class Current: 370/335
• CPC Class Codes: H04B 1/7075 with code phase acquisition
• CPC Class Codes: H04B 1/70754 Setting of search window, i.e. range of code offsets to be searched H04B1/70758 takes precedence
• CPC Class Codes: H04B 2001/70706 using a code tracking loop, e.g. a delay locked loop
• CPC Class Codes: H04B 2201/70703 using multiple or variable rates
• CPC Class Codes: H04B 2201/70709 with discontinuous detection
• CPC Class Codes: H04B 2201/70715 with application-specific features
• CPC Class Codes: H04B 7/2628 using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA] H04B7/2618 takes precedence
• CPC Class Codes: H04J 13/0022 PN, e.g. Kronecker
• CPC Class Codes: H04J 13/004 Orthogonal
• CPC Class Codes: H04J 13/16 Code allocation
• CPC Class Codes: H04J 13/18 Allocation of orthogonal codes
• CPC Class Codes: H04L 1/0007 by modifying the frame length
• CPC Class Codes: H04L 1/165 Variable formats
• CPC Class Codes: H04L 1/1809 Selective-repeat protocols
• CPC Class Codes: H04L 25/14 Channel dividing arrangements , i.e. in which a single bit stream is divided between several baseband channels and reassembled at the receiver
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 7/06 the synchronisation signals differing from the information signals in amplitude, polarity or frequency or length
• CPC Class Codes: H04Q 11/0428 Integrated services digital network, i.e. systems for transmission of different types of digitised signals, e.g. speech, data, telecentral, television signals
• CPC Class Codes: H04Q 2213/13098 Mobile subscriber
• CPC Class Codes: H04Q 2213/13202 Network termination [NT]
• CPC Class Codes: H04Q 2213/13204 : Protocols
• CPC Class Codes: H04Q 2213/13209 : ISDN
• CPC Class Codes: H04Q 2213/13216 : Code signals, frame structure
• CPC Class Codes: H04Q 2213/1327 : Release and resetting of connection
• CPC Class Codes: H04Q 2213/13298 : Local loop systems, access network
• CPC Class Codes: H04Q 2213/13332 : Broadband, CATV, dynamic bandwidth allocation
• CPC Class Codes: H04Q 2213/1336 : Synchronisation
• CPC Class Codes: H04Q 2213/13389 : LAN, internet
• CPC Class Codes: H04W 24/00 : Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 28/20 : Negotiating bandwidth
• CPC Class Codes: H04W 28/22 : Negotiating communication rate
• CPC Class Codes: H04W 56/00 : Synchronisation arrangements
• CPC Class Codes: H04W 56/0045 : compensating for timing error by altering transmission time
• CPC Class Codes: H04W 56/0075 : based on arrival time vs. expected arrival time
• CPC Class Codes: H04W 72/044 : based on the type of the allocated resource
• CPC Class Codes: H04W 72/0446 : Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/0453 : Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/0466 : the resource being a scrambling code
• CPC Class Codes: H04W 72/21 : in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 74/00 : Wireless channel access
• CPC Class Codes: H04W 74/04 : Scheduled access hybrid access H04W74/02
• CPC Class Codes: H04W 76/28 : Discontinuous transmission [DTX]; Discontinuous reception [DRX]
• CPC Class Codes: H04W 84/14 : WLL [Wireless Local Loop]; RLL [Radio Local Loop]

Abstract

A service option overlay for a CDMA wireless communication in which multiple allocatable subchannels are defined on a reverse link by assigning different code phases of a given long pseudonoise (PN) code to each subchannel. The instantaneous bandwidth needs of each on-line subscriber unit are then met by dynamically allocating none, one, or multiple subchannels on an as needed basis for each network layer connection. The system efficiently provides a relatively large number of virtual physical connections between the subscriber units and the base stations on the reverse link for extended idle periods such as when computers connected to the subscriber units are powered on, but not presently actively sending or receiving data. These maintenance subchannels permit the base station and the subscriber units to remain in phase and time synchronism in an idle mode and also request additional channels. This in turn allows fast acquisition of additional subchannels as needed by allocating new code phase subchannels. Preferably, the code phases of the new channels are assigned according to a predetermined code phase relationship with respect to the code phase of the corresponding maintenance subchannel.

Claims

1. A subscriber unit comprising:

a transceiver configured to establish a communication link with a base station;

wherein the transceiver is further configured to transmit data to the base station over a plurality of code division multiple access (CDMA) channels;

wherein the transceiver is further configured to receive control information from a base station; and

wherein the transceiver is further configured, in response to the control information, to transmit a single CDMA channel, having a burst pattern, in at least one time slot and not transmit any CDMA channels in other time slots.

2. The subscriber unit as in claim 1 wherein the transceiver is further configured, in response to not receiving the control information, to transmit the plurality of CDMA channels in all time slots.

3. The subscriber unit as in claim 1 wherein a number of the CDMA channels used to transmit the data varies.

4. The subscriber unit as in claim 1 wherein the plurality of CDMA channels and the single CDMA channel are derived from at least one pseudonoise (PN) code.

5. The subscriber unit as in claim 1 wherein the burst pattern is transmitted using a minimum set of time slots in which the transceiver transmits the burst pattern to maintain synchronization.

6. A method comprising:

establishing by a subscriber unit a communication link with a base station;

transmitting by the subscriber unit data to the base station over a plurality of code division multiple access (CDMA) channels;

receiving by the subscriber unit control information from a base station; and

transmitting by the subscriber unit, in response to the control information, a single CDMA channel, having a burst pattern, in at least one time slot and not transmit any CDMA channels in other time slots.

7. The method as in claim 6 wherein in response to not receiving the control information, transmitting by the subscriber unit the plurality of CDMA channels in all time slots.

8. The method as in claim 6 wherein a number of the CDMA channels used to transmit the data varies.

9. The method as in claim 6 wherein the plurality of CDMA channels and the single CDMA channel are derived from at least one pseudonoise (PN) code.

10. The method as in claim 6 wherein the burst pattern is transmitted in a minimum set of time slots in which the transceiver transmits the burst pattern to maintain synchronization.

11. A base station comprising:

a transceiver configured to establish a communication link with a subscriber unit;

wherein the transceiver further is configured to receive data over a plurality of code division multiple access (CDMA) channels from the subscriber unit;

wherein the transceiver is further configured to transmit control information to the subscriber unit; and

wherein the transceiver is further configured to receive, in response to transmitting the control information, a single CDMA channel, having a burst pattern, in at least one time slot and not receiving any CDMA channels in other time slots from the subscriber unit.

12. The base station as in claim 11 wherein the transceiver is further configured, in response to not transmitting the control information, to receive the plurality of CDMA channels in all time slots.

13. The base station as in claim 11 wherein a number of the CDMA channels used to receive the data varies.

14. The base station as in claim 11 wherein the plurality of CDMA channels and the single CDMA channel are derived from at least one pseudonoise (PN) code.

15. The base station as in claim 11 wherein the burst pattern is received in a minimum set of time slots to maintain synchronization with the subscriber unit.