Transmitter control in communication systems

• US 8,644,371 B2
• Filed: 12/28/2012
• Issued: 02/04/2014
• Est. Priority Date: 03/10/2009
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Mezer, Amir, Ran, Adee
• Primary Examiner(s): Patel, Dhaval
• Application Number:
  US13/729,520
• Publication Number:
  US 20130136161A1
• Time in Patent Office: 403 Days
• Field of Search: 375/229, 375/230, 375/231, 375/232, 375/257, 708/300, 708/819, 333/18
• US Class Current: 375/232
• CPC Class Codes: H04L 2025/03356 Baseband transmission
• CPC Class Codes: H04L 2025/03808 Transmission of equaliser coefficients
• CPC Class Codes: H04L 25/03343 Arrangements at the transmitter end
• CPC Class Codes: H04L 27/01 Equalisers baseband equalizers at the transmitter end H04L25/03343; in analogue transmission systems H04B3/04, H04B7/005

Abstract

Techniques are described to adaptively adjust the equalizer settings of each transmitter in a transmitter-receiver pair. The transmitter-receiver pair can be used at least with implementations that comply with 40GBASE-CR4 or 100GBASE-CR10. For implementations that comply with 40GBASE-CR4, equalizer settings of four transmitters may be independently established.

Claims

1. A transceiver comprising:

a first transmitter;

a first receiver;

a second transmitter; and

a second receiver, wherein;

the first transmitter comprises an equalizer, wherein the equalizer is in compliance with one or more of clauses 72.7.1.10 and 72.7.1.11 of IEEE Std 802.3ap-2007 and wherein electrical characteristics of the first transmitter are in compliance with clause 72.7.1 of IEEE Std 802.3ap-2007;

the first receiver comprises;

clock and data recovery logic to determine error properties of a signal received from a third transmitter;

control channel decoder to decode control signals received from the third transmitter;

remote transmit adaptation engine to determine equalizer settings of an equalizer of the third transmitter based in part on the error properties and the control signals; and

a transmit control logic to request to adjust settings applied by the equalizer of the first transmitter, the settings received from the third transmitter;

the second transmitter comprises an equalizer, wherein the equalizer is in compliance with one or more of clauses 72.7.1.10 and 72.7.1.11 of IEEE Std 802.3ap-2007 and wherein electrical characteristics of the second transmitter are in compliance with clause 72.7.1 of IEEE Std 802.3ap-2007;

the second receiver comprises;

clock and data recovery logic to determine error properties of a signal received from a fourth transmitter;

control channel decoder to decode control signals received from the fourth transmitter;

remote transmit adaptation engine to determine equalizer settings of an equalizer of the fourth transmitter based in part on the error properties and the control signals; and

a transmit control logic to request to adjust settings applied by the equalizer of the second transmitter, the settings received from the fourth transmitter; and

the remote transmit adaptation engine of the first receiver and the remote transmit adaptation engine of the second receiver are to independently determine equalizer settings of the third and fourth transmitters.

2. The transceiver of claim 1, further comprising:

logic to cause transmission of the equalizer settings of the third transmitter and

logic to receive an indication of whether transmitted equalizer settings of the third transmitter were applied by the third transmitter.

3. The transceiver of claim 1, further comprising:

logic to cause transmission of the equalizer settings of the fourth transmitter and

logic to receive an indication of whether transmitted equalizer settings of the fourth transmitter were applied by the fourth transmitter.

4. The transceiver of claim 1, wherein:

the control channel decoder of the first receiver is to decode received signals from the third transmitter to determine whether the determined equalizer settings of the equalizer of the third transmitter are applied and

the control channel decoder of the second receiver is to decode received signals from the fourth transmitter to determine whether the determined equalizer settings of the equalizer of the fourth transmitter are applied.

5. The transceiver of claim 1, wherein:

the transmit control logic of the first receiver comprises;

logic to request to adjust equalizer settings of the first transmitter using a first control channel in compliance with 10GBASE-KR PMD control function defined in clause 72.6.10 of IEEE Std 802.3ap-2007 and

the transmit control logic of the second receiver comprises;

logic to request to adjust equalizer settings of the second transmitter using a second control channel in compliance with 10GBASE-KR PMD control function defined in clause 72.6.10 of IEEE Std 802.3ap-2007.

6. The transceiver of claim 1, further comprising:

a lane input that is to provide communicatively coupling capability to lanes, the lanes to provide signal transmission in accordance with 10GBASE-KR of IEEE Std 802.3ap-2007.

7. The transceiver of claim 6, wherein:

when lanes are communicatively coupled to the lane input, an aggregate data rate received by the transceiver comprises a product of (i) a number of lanes communicatively coupled to the transceiver and (ii) a transmission rate specified in 10GBASE-KR of IEEE 802.3ap (2007).

8. The transceiver of claim 1, wherein the equalizers of the first and second transmitter are selected from among:

Continuous-Time Linear Equalizers (CTLE), finite impulse response filter, and Digital Infinite Impulse Response (IIR) filter.

9. The transceiver of claim 8, further comprising:

logic to select an equalizer of the first transmitter based on a communication from a third transmitter and

logic to select an equalizer of the second transmitter based on a communication from a fourth transmitter.

10. The transceiver of claim 1, wherein

the remote transmit adaptation engine of the first receiver and the remote transmit adaptation engine of the second receiver are to determine equalizer settings after a determination of a number of utilized transmit-receive pairs.

11. A method comprising:

determining first equalizer settings of a first transmitter of a first signal based in part on error properties of the first signal using clock and data recovery for the first signal and also based in part on control signals from the first transmitter determined using a first control channel decoding, wherein the first equalizer used by the first transmitter is in compliance with one or more of clauses 72.7.1.10 and 72.7.1.11 of IEEE Std 802.3ap-2007;

determining second equalizer settings of a second transmitter of a second signal based in part on error properties of the second signal using clock and data recovery for the second signal and also based in part on control signals from the second transmitter determined using a control channel decoding, wherein the second equalizer used by the second transmitter is in compliance with one or more of clauses 72.7.1.10 and 72.7.1.11 of IEEE Std 802.3ap-2007 and wherein determining first equalizer settings is independent from determining second equalizer settings;

requesting to adjust settings applied by the first equalizer of the first transmitter; and

requesting to adjust settings applied by the second equalizer of the second transmitter.

12. The method of claim 11, further comprising:

receiving an indication of whether the transmitted first equalizer settings were applied by the first transmitter and

receiving an indication of whether the transmitted second equalizer settings were applied by the second transmitter.

13. The method of claim 11, further comprising:

receiving third equalizer settings;

receiving fourth equalizer settings;

requesting application of third equalizer settings by a third transmitter using a control channel in compliance with a 10GBASE-KR PMD control function defined in clause 72.6.10 of IEEE Std 802.3ap-2007; and

requesting application of fourth equalizer settings by a fourth transmitter using a control channel in compliance with a 10GBASE-KR PMD control function defined in clause 72.6.10 of IEEE Std 802.3ap-2007.

14. The method of claim 11, further comprising:

receiving a selection of an equalizer of a third transmitter and

receiving a selection of an equalizer of a fourth transmitter.

15. The method of claim 14, wherein the equalizer of the third transmitter and the equalizer of the fourth transmitter are selected from among:

Continuous-Time Linear Equalizers (CTLE), finite impulse response filter, and Digital Infinite Impulse Response (IIR) filter.

16. The method of claim 11, further comprising:

selecting an equalizer of the first transmitter;

selecting an equalizer of the second transmitter;

transmitting the equalizer selection of the first transmitter; and

transmitting the equalizer selection of the second transmitter.

17. The method of claim 16, wherein the equalizer of the first transmitter and the second equalizer of the second transmitter are selected from among:

Continuous-Time Linear Equalizers (CTLE), finite impulse response filter, and Digital Infinite Impulse Response (IIR) filter.

18. The method of claim 11, further comprising:

communicatively coupling lanes, wherein an aggregate data rate received over the lanes comprises a product of (i) a number of lanes communicatively coupled to the transceiver and (ii) a transmission rate specified in 10GBASE-KR of IEEE 802.3ap (2007).

19. The method of claim 11, wherein determining first equalizer settings and determining second equalizer settings occur after a number of utilized transmit-receive pairs is known.