Dynamic channel quality measurement procedure implemented in a wireless digital communication system to prioritize the forwarding of downlink data

• US 20070117519A1
• Filed: 01/23/2007
• Published: 05/24/2007
• Est. Priority Date: 05/14/2001
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Zeira, Eldad, Zeira, Ariela, Terry, Stephen, Miller, James, Dick, Stephen
• Granted Patent: US 7,639,989 B2
• Time in Patent Office: Days
• US Class Current: 455/69
• CPC Class Codes: H04B 17/24 with feedback of measurements to the transmitter
• CPC Class Codes: H04B 17/309 Measuring or estimating channel quality parameters
• CPC Class Codes: H04B 17/382 for resource allocation, admission control or handover
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0027 Scheduling of signalling, e.g. occurrence thereof
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 72/543 based on requested quality, e.g. QoS
• CPC Class Codes: H04W 72/56 based on priority criteria

Abstract

A wireless digital communication system includes a base station in communication with a plurality of user equipment mobile terminals (UEs). The system prioritizes the forwarding of blocks of downlink data to designated ones of the UEs. The system employs adaptive modulation and coding (AM&C) to achieve improved radio resource utilization and provides optimum data rates for user services. Blocks of downlink (DL) data are received by the base station which requests downlink (DL) channel quality measurements only from those mobile terminals (UEs) with pending downlink transmissions. The UEs respond to the request by measuring and reporting DL channel quality to the base station, which then allocates resources such that the UEs will make best use of radio resources. The base station notifies the UEs of the physical channel allocation indicating the modulation/coding rate and allocated slots followed by transmission of blocks of downlink data which are transmitted to the UEs.

Claims

1. A wireless digital communication system for prioritizing the forwarding of blocks of downlink data, the system including a base station and a plurality of user equipment mobile terminals (UEs), wherein a first subset of the UEs have pending downlink transmissions and a second subset of the UEs do not have pending downlink transmissions, the system comprising:

(a) means for the base station to receive blocks of downlink data for distribution to designated ones of the plurality of UEs in the first subset; and

(b) means for the base station to transmit to each of the designated UEs in the first subset a request to begin downlink channel quality measurements, whereby the base station does not transmit a request to begin downlink channel quality measurements to the UEs in the second subset due to not having pending downlink transmissions.

2. The system of claim 1 further comprising:

(c) means for each of the designated UEs in the first subset to perform the downlink channel quality measurements;

(d) means for each of the designated UEs in the first subset to transmit the results of the downlink channel quality measurements to the base station;

(e) means for the base station to establish a priority for the designated UEs in the first subset based on the results of the downlink channel quality measurements;

(f) means for the base station to transmit an allocation signal to each of the designated UEs in the first subset;

(g) means for each of the designated UEs in the first subset to set up transmission parameters in response to the allocation signal; and

(h) means for the base station to transmit the downlink data to the designated UEs in the first subset in accordance with the established priority.

3. The system of claim 2 wherein the allocation signal indicates a particular coding rate, modulation type and at least one allocated time slot.

4. The system of claim 2 further comprising means for the base station to transmit a downlink physical channel allocation signal to the UE associated with the highest downlink channel quality measurement.

5. In a wireless digital communication system including a base station and plurality of user equipment mobile terminals (UEs), wherein a first subset of the UEs have pending downlink transmissions and a second subset of the UEs do not have pending downlink transmissions, a method for prioritizing the forwarding of blocks of downlink data, the method comprising:

(a) the base station receiving blocks of downlink data for distribution to designated ones of the plurality of UEs in the first subset; and

(b) the base station transmitting to each of the designated UEs in the first subset a request to begin downlink channel quality measurements, whereby the base station does not transmit a request to begin downlink channel quality measurements to the UEs in the second subset due to not having pending downlink transmissions.

6. The method of claim 5 further comprising:

(c) each of the designated UEs in the first subset performing the downlink channel quality measurements;

(d) each of the designated UEs in the first subset transmitting the results of the downlink channel quality measurements to the base station;

(e) the base station establishing a priority for the designated UEs in the first subset based on the results of the downlink channel quality measurements;

(f) the base station transmitting an allocation signal to each of the designated UEs in the first subset;

(g) each of the designated UEs in the first subset setting up transmission parameters in response to the allocation signal; and

(h) the base station transmitting the downlink data to the designated UEs in the first subset in accordance with the established priority.

7. The method of claim 6 wherein the allocation signal indicates a particular coding rate, modulation type and at least one allocated time slot.

8. The method of claim 6 further comprising the base station transmitting a downlink physical channel allocation signal to the UE associated with the highest downlink channel quality measurement.