Dynamic channel quality measurement procedure implemented by a base station for adaptive modulation and coding techniques

• US 6,909,901 B2
• Filed: 01/30/2004
• Issued: 06/21/2005
• Est. Priority Date: 05/14/2001
• Status: Expired due to Term

• Current Assignee: Apple Inc.
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Zeira, Eldad, Dick, Stephen G., Terry, Stephen E., Miller, James M., Zeira, Ariela
• Primary Examiner(s): Miloro, Marceau
• Application Number:
  US10/768,211
• Publication Number:
  US 20040185788A1
• Time in Patent Office: 508 Days
• Field of Search: 455/62, 455/67.11, 455/102, 455/450, 455/452.1, 455/456.5, 455/509, 455/512, 455/452.2
• US Class Current: 455/452.2
• 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 method for a base station to optimize radio resource utilization and adjust data rates in a wireless digital communications system. The base station communicates with a plurality of user equipment mobile terminals (UEs) and employs adaptive modulation and coding (AM&C) to achieve improved radio resource utilization and provide 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 method implemented by a base station to optimize the transfer of downlink data in a wireless communication system including a plurality of mobile terminals (MTs), the method comprising:

(a) the base station receiving blocks of downlink data designated for transmission to at least one of the MTs;

(b) the base station transmitting a request for the at least one MT to perform a downlink channel quality measurement in response to step (a);

(c) the base station receiving the requested downlink channel quality measurement from the at least one MT;

(d) the base station allocating a plurality of radio resources to the at least one MT in response to step (c); and

(e) the base station transmitting the designated blocks of downlink data to the at least one MT in accordance with the allocation of step (d).

2. The method of claim 1 wherein the base station determines which timeslot(s) to use for transmitting the designated blocks of downlink data.

3. The method of claim 1 further comprising:

(f) the base station indicating to the at least one MT a particular coding rate, modulation type and allocated timeslots.

4. A method implemented by a base station to optimize the transfer of downlink data in a wireless communication system including a plurality of mobile terminals (MTs), the method comprising:

(a) the base station receiving blocks of downlink data designated for transmission to the plurality of MTs;

(b) the base station transmitting a request for each respective MT to perform a downlink channel quality measurement in response to step (a);

(c) the base station receiving the requested downlink channel quality measurements from the plurality of MTs;

(d) the base station determining which of the MTs will most efficiently use radio resources based on the received downlink channel quality measurements;

(e) the base station signaling coding rate, modulation type and time slot information to each of the MTs;

(f) the base station establishing a data transfer priority for each of the MTs; and

(g) the base station transmitting the designated blocks of downlink data to each of the plurality of MTs in accordance with the signaled information of step (e) and the priority of step (f).

5. A method implemented by a base station to optimize the transfer of downlink data in a wireless communication system including a plurality of mobile terminals (MTs), the method comprising:

(a) the base station receiving blocks of downlink data designated for transmission to given ones of the MTs;

(b) the base station transmitting a request for each of the given MTs to perform a downlink channel quality measurement;

(c) the base station receiving the requested downlink channel quality measurements from each of the given MTs;

(d) the base station determining preferred ones of the given ones of MTs which are capable of making best use of a plurality of radio resources;

(e) the base station allocating timeslots to be used by the preferred MTs; and

(f) the base station transmitting the designated blocks of downlink data to the given MTs in accordance with the allocated timeslots after the given MTs respond to the request.

6. A method implemented by a base station to optimize the transfer of downlink data in a wireless communication system including a plurality of mobile terminals (MTs), the method comprising:

(a) the base station receiving blocks of downlink data designated for transmission to given ones of the MTs;

(b) the base station determining preferred ones of the given ones of the MTs which are capable of making best use of a plurality of radio resources responsive to the downlink channel quality measurements received from the given ones of the MTs;

(c) the base station allocating a given number of timeslots to the preferred MTs according to the downlink channel quality measurements and the amount of downlink data available for transmission to the given MTs; and

(d) the base station transmitting the designated blocks of downlink data to the given MTs in accordance with the allocated timeslots after the given MTs respond to the request.

7. A base station for optimizing the transfer of downlink data in a wireless communication system including a plurality of mobile terminals (MTs), the base station comprising:

(a) means for receiving blocks of downlink data designated for transmission to at least one of the MTs;

(b) means for transmitting a request for the at least one MT to perform a downlink channel quality measurement in response to receiving blocks of downlink data designated for transmission to at least one of the MTs;

(c) means for receiving the requested downlink channel quality measurement from the at least one MT;

(d) means for allocating a plurality of radio resources to the at least one MT in response to receiving the requested downlink channel quality measurement from the at least one MT; and

(e) means for transmitting the designated blocks of downlink data to the at least one MT in accordance with the allocating means.

8. The base station of claim 7 wherein the base station determines which timeslot(s) to use for transmitting the designated blocks of downlink data.

9. The base station of claim comprising:

(f) means for indicating to the at least one MT a particular coding rate, modulation type and allocated timeslots.

10. A base station for optimizing the transfer of downlink data in a wireless communication system including a plurality of mobile terminals (MTs), the base station comprising:

(a) means for receiving blocks of downlink data designated for transmission to the plurality of MTs;

(b) means for transmitting a request for each respective MT to perform a downlink channel quality measurement in response to receiving blocks of downlink data designated for transmission to the plurality of MTs;

(c) means for receiving the requested downlink channel quality measurements from the plurality of MTs;

(d) means for determining which of the MTs will most efficiently use radio resources based on the received downlink channel quality measurements;

(e) means for signaling coding rate, modulation type and time slot information to each of the MTs;

(f) means for establishing a data transfer priority for each of the MTs; and

(g) means for transmitting the designated blocks of downlink data to each of the plurality of MTs in accordance with the signaling means and the establishing means.

11. A base station for optimizing the transfer of downlink data in a wireless communication system including a plurality of mobile terminals (MTs), the base station comprising:

(a) means for receiving blocks of downlink data designated for transmission to given ones of the MTs;

(b) means for transmitting a request for each of the given MTs to perform a downlink channel quality measurement;

(c) means for receiving the requested downlink channel quality measurements from each of the given MTs;

(d) means for determining preferred ones of the given ones of MTs which are capable of making best use of a plurality of radio resources;

(e) means for allocating timeslots to be used by the preferred MTs; and

(f) means for transmitting the designated blocks of downlink data to the given MTs in accordance with the allocated timeslots after the given MTs respond to the request.

12. A base station for optimizing the transfer of downlink data in a wireless communication system including a plurality of mobile terminals (MTs), the base station comprising:

(a) means for receiving blocks of downlink data designated for transmission to given ones of the MTs;

(b) means for determining preferred ones of the given ones of the MTs which are capable of making best use of a plurality of radio resources responsive to the downlink channel quality measurements received from the given ones of the MTs;

(c) means for allocating a given number of timeslots to the preferred MTs according to the downlink channel quality measurements and the amount of downlink data available for transmission to the given MTs; and

(d) means for transmitting the designated blocks of downlink data to the given MTs in accordance with the allocated timeslots after the given MTs respond to the request.