Adaptive channel measurement reporting

• US 8,036,327 B2
• Filed: 12/19/2003
• Issued: 10/11/2011
• Est. Priority Date: 12/19/2003
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Wiberg, Niclas, Furuskar, Anders
• Primary Examiner(s): Payne; David C.
• Assistant Examiner(s): Haider; Syed
• Application Number:
  US10/596,613
• Publication Number:
  US 20070064772A1
• Time in Patent Office: 2,853 Days
• Field of Search: 375/140, 375/144, 375/230, 375/232, 375/267, 375/340, 375/341, 375/343, 375/346, 375/349, 375/350, 375/260, 455/59, 455/69, 455/115.1, 455/522, 455/213, 455/232.1, 455/334
• US Class Current: 375/350
• CPC Class Codes: H04B 17/20 of receivers
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 2025/03802 Signalling on the reverse channel
• CPC Class Codes: H04L 25/0212 of impulse response
• CPC Class Codes: H04L 25/022 of frequency response
• CPC Class Codes: H04L 25/0236 using estimation of the other symbols

Abstract

The present invention relates to a method, arrangements, and a message format for achieving an improved and adaptive reporting of measurements for a communication channel between a transmitter and a receiver unit. The invention achieves a message format for providing detailed channel information to a transmitter unit but requiring a minimized amount of transmission capacity. The receiver unit delivers preferably incremental updatings of the filter function, represented in the time- or frequency domain, of the entire channel between transmitter and receiver. For this purpose the channel representing function is divided into a number of sub-functions, a function of which corresponding to the true channel filter function, and whereof the various sub-functions contain channel information of a ranked degree of significance.

Claims

1. A method in a receiver unit to receive communication signals from a transmitter unit via a multi-path channel, said method comprising the steps of:

estimating parameters of a channel filter function of said channel from said received communication signals from the transmitter unit;

sub-dividing the channel filter function into two or more parts, a function of which representing an approximation of the estimated full channel filter function;

representing the complex parameters of at least a selection of said parts of the channel filter function as actual parameter values, or as incremental values indicating the difference to a reference value; and

,

composing a channel measurement message to be transmitted to the transmitter unit of a portion including said parameter representations and a portion indicating the manner of representing said parameters.

2. The method according to claim 1, wherein said function performs a summing of the sub-divided parts of the channel filter function.

3. The method according to claim 1, wherein the sub-divided parts of the channel filter function comprise channel information of a ranked degree of significance.

4. The method according to claim 1, wherein the channel filter function is represented as a channel impulse response in the time-domain.

5. The method according to claim 4, wherein the complex parameters of the channel impulse response are reproduced as amplitude and phase values.

6. The method according to claim 4, wherein the primary sub-divided filter function includes a representation of one or more of the most significant channel components.

7. The method according to claim 6, wherein the most significant channel component is the component having the shortest delay.

8. The method according to claim 1, wherein the channel filter function is represented as a channel frequency response in the frequency-domain.

9. The method according to claim 8, wherein a complex parameter of the channel frequency response is reproduced at least as an amplitude value and optionally by an additional phase value.

10. The method according to claim 1, wherein the complex parameters of said parts of the channel filter function are represented by their actual values in case of a significant change compared to a previous reference value.

11. The method according to claim 10, wherein the reference value corresponds to a previous channel parameter representation.

12. The method according to claim 10, wherein the reference value corresponds to a modelled estimate of the channel filter function.

13. The method according to claim 12, wherein the modelled estimate is a interpolation of the channel filter function from the complex parameters of the channel filter function.

14. The method according to claim 12, wherein said modelled estimate of the channel filter function has been received by the transmitter unit.

15. An apparatus for processing communication signals received via a multipath channel, comprising:

means for estimating parameters of a channel filter function of said channel from said received communication signals from the transmitter unit;

means for sub-dividing the channel filter function into two or more parts, a function of which representing the estimated full channel filter function;

means for representing the complex parameters of at least a selection of the sub-divided channel filter function as actual parameter values, or as incremental values indicating the difference to a reference value; and

,

means for composing a channel measurement message to be transmitted to the transmitter unit including said set of parameter representations and a header field indicating the manner of representing said parameters.

16. The apparatus according to claim 15, which is integrated in a mobile user equipment.