Maintaining a maintenance channel in a reverse link of a wireless communications system

• US 20040047328A1
• Filed: 01/08/2003
• Published: 03/11/2004
• Est. Priority Date: 01/08/2002
• Status: Active Grant

• Current Assignee: IPR Licensing Incorporated (InterDigital, Inc.)
• Original Assignee: Tantivy Communications Incorporated (InterDigital, Inc.)
• Inventors: Proctor, James A. Jr., Nelson, George Rodney Jr.
• Granted Patent: US 8,605,702 B2
• Time in Patent Office: Days
• US Class Current: 370/342
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/12 Outer and inner loops
• CPC Class Codes: H04W 52/18 TPC being performed according to specific parameters
• CPC Class Codes: H04W 52/287 when the channel is in stand-by
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling
• CPC Class Codes: H04W 74/04 Scheduled access hybrid access H04W74/02
• CPC Class Codes: H04W 74/0866 using a dedicated channel for access
• CPC Class Codes: H04W 76/25 Maintenance of established connections
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

In a reverse link of a wireless CDMA communication system, a method of maintaining an idling mode connection between a field unit and a base transceiver station is provided using various techniques to maintain the idle mode connection at a reduced power level. A preferred embodiment computes a time slot or frame offset based on modulo function using a field unit identifier in order to distribute field unit maintenance transmissions among available slots or offsets. An alternate embodiment detects explicit signaling states changes at the physical layer and causes power target changes. A further embodiment transmits maintenance data during predetermined time intervals, coordinated between the field units and BTS, allowing power levels to be adjusted accordingly.

Claims

1. A method for maintaining an idling mode connection between a field unit and a base transceiver station in a reverse link of a wireless Code Division Multiple Access communication system, comprising:

determining an identifier corresponding to the field unit;

applying a modulo function to the identifier to compute a slot in the reverse link in which the field unit can transmit a message or a signal; and

transmitting the message or the signal to the base transceiver station in the computed slot.

2. The method of claim 1 wherein the computed time slot is one of the gated-on periods of a gated reverse pilot channel.

3. The method of claim 1 wherein the computed time slot is one of the 128 slots defined by I-CDMA.

4. The method of claim 1 wherein the identifier is a MAC_ID.

5. The method of claim 1 wherein the wherein the message contains maintenance data.

6. The method of claim 1 wherein the message contains user payload data.

7. The method of claim 1 further comprising defining the modulo function based on how many time division multiplexed slots are defined in the wireless Code Division Multiple Access communication system.

8. The method of claim 1 wherein transmitting the message is performed for at least one of:

pilot only transmissions, transmissions with overhead signaling, and payload transmissions.

9. The method of claim 1 further comprising applying a different modulo function to different field units depending on the different field units=gated rate.

10. The method of claim 1 further comprising assigning the identifier with regard to the time division multiplexed effect on the reverse link, in a manner consistent with at least one of a linear fashion, with regard to the time division multiplexed effect on the reverse link, based on making the number of occupants in each slot equal, and assigning a next identifier to result in an addition to the minimum occupied modulo state.

11. The method of claim 1 further comprising periodically re-assigning the identifiers to more optimally distribute the field units into time division multiplexed slots.

12. A method for maintaining an idling mode connection between a field unit and a base transceiver station in a reverse link of a wireless Code Division Multiple Access communication system, comprising:

determining a reverse link state change is needed between a plurality of states;

transmitting a request for the reverse link state change at the physical layer;

detecting the request transmitted at the physical layer; and

changing the power control targets in the base transceiver station when changing states.

13. The method of claim 12 wherein the plurality of states includes:

active, control hold and dormant states.

14. The method of claim 12 wherein the plurality of states includes:

active, standby and idle states.

15. The method of claim 12 wherein the transmitting a request step and the detecting the request step occur at the link layer.

16. A method for maintaining an idling mode connection between a field unit and a base transceiver station in a reverse link of a wireless Code Division Multiple Access communication system, comprising:

obtaining a predetermined interval for transmission of data;

coordinating between the base station transceiver and the field unit such that the predetermined interval is common to both;

adjusting a transmitting power level at regular cycles according to the predetermined interval;

transmitting, at the adjusted power level, the data from the field unit to the base transceiver station; and

adjusting, at the base transceiver station, a reference signal quality level in response to the adjusted transmitting power level.