Impairment monitoring apparatus, impairment monitoring and compensating system and method

• US 10,644,791 B2
• Filed: 02/28/2019
• Issued: 05/05/2020
• Est. Priority Date: 04/09/2018
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Liang, Junpeng, Fan, Yangyang, Tao, Zhenning
• Primary Examiner(s): Cors, Nathan M
• Application Number:
  US16/288,181
• Publication Number:
  US 20190312637A1
• Time in Patent Office: 432 Days
• CPC Class Codes: H04B 10/0779 Monitoring line transmitter or line receiver equipment
• CPC Class Codes: H04B 10/0795 Performance monitoring; Measurement of transmission parameters
• CPC Class Codes: H04B 10/5561 Digital phase modulation
• CPC Class Codes: H04B 10/58 Compensation for non-linear transmitter output
• CPC Class Codes: H04B 10/6163 Compensation of non-linear effects in the fiber optic link, e.g. self-phase modulation [SPM], cross-phase modulation [XPM], four wave mixing [FWM]
• CPC Class Codes: H04B 10/697 Arrangements for reducing noise and distortion
• CPC Class Codes: H04B 17/14 of the whole transmission and reception path, e.g. self-test loop-back
• CPC Class Codes: H04B 17/21 for calibration; for correcting measurements
• CPC Class Codes: H04B 3/32 Reducing cross-talk, e.g. by compensating
• CPC Class Codes: H04L 2025/03426 transmission using multiple-input and multiple-output channels
• CPC Class Codes: H04L 25/03968 mean-square error [MSE]

Abstract

Embodiments of this disclosure provide an impairment monitoring apparatus, impairment monitoring and compensating system and method. As a parameter of a impairment of a receiver end and/or a parameter of an impairment of a transmitter end is/are determined according to a preset period or a preset condition to perform compensation or calibration, complexity of calculation and power consumption of the system may be efficiently lowered. And as the parameter of the impairment of the receiver end and the parameter of the impairment of the transmitter end are not changed rapidly, determining these parameters according to the preset period or the preset condition to perform compensation or calibration will not affect an effect of the compensation or calibration, thereby ensuring a performance of the system.

Claims

1. An impairment monitoring apparatus, provided in a receiver end apparatus, the receiver end apparatus comprising:

a first monitor to,

determine a parameter of an impairment in communication performance of the receiver end apparatus according to a set period or a set condition, and

transmit the parameter of the impairment of the receiver end apparatus to a first compensator to compensate for the impairment of the receiver end apparatus in a received signal, and/or

transmit the parameter of the impairment of the receiver end apparatus to a management device to cause the management device to analyze a cause of the impairment and/or calibrate the receiver end apparatus according to the parameter of the impairment of the receiver end apparatus; and

/or

a second monitor to,

determine a parameter of an impairment in communication performance of a transmitter end apparatus according to a set period or a set condition, and

transmit the parameter of the impairment of the transmitter end apparatus to a second compensator to compensate for the impairment of the transmitter end apparatus in the received signal, and/or

transmit the parameter of the impairment of the transmitter end apparatus to the management device to cause the management device analyze a cause of the impairment and/or calibrate the transmitter end apparatus according to the parameter of the impairment of the transmitter end apparatus,

wherein,

when determining the parameter of the impairment of the receiver end apparatus, the first monitor is to,

determine a first filter coefficient according to a pilot signal inserted into a transmission signal, and

take the first filter coefficient and/or a parameter obtained through a calculation according to the first filter coefficient as the parameter of the impairment of the receiver end apparatus; and

when determining the parameter of the impairment of the transmitter end apparatus, the second monitor is to,

determine a second filter coefficient according to a pilot signal inserted into a transmission signal, and

take the second filter coefficient and/or a parameter obtained through a calculation according to the second filter coefficient as the parameter of the impairment of the transmitter end apparatus.

2. The apparatus according to claim 1, wherein,

coefficients on a leading diagonal in the first filter coefficient denote differences of amplitude-frequency responses and phase-frequency responses between signals of paths of the receiver end apparatus, and coefficients on an off-diagonal denote distribution and magnitudes of frequencies of crosstalk between the signals of paths of the receiver end apparatus.

3. The apparatus according to claim 1, wherein the pilot signal is a constant modulus signal.

4. The apparatus according to claim 1, wherein,

the first monitor is an MIMO monitor based on a blind equalization algorithm;

and

the second monitor is an MIMO monitor based on a minimum mean square error algorithm or a least-mean-square algorithm.

5. A system, comprising:

a first compensator to,

determine a parameter of an impairment in communication performance of a receiver end apparatus according to a set period or a set condition, and

compensate for the impairment of the receiver end apparatus in a received signal according to the parameter of the impairment of the receiver end apparatus, and/or

analyze a cause of the impairment and/or calibrate the receiver end apparatus according to the parameter of the impairment of the receiver end apparatus; and

/or

a second compensator to,

determine a parameter of an impairment in communication performance of a transmitter end apparatus according to a set period or a set condition, and

compensate for the impairment of the transmitter end apparatus in the received signal according to the parameter of the impairment of the transmitter end apparatus, and/or

analyze a cause of the impairment and/or calibrate the transmitter end apparatus according to the parameter of the impairment of the transmitter end apparatus,

wherein, when determining the parameter of the impairment of the receiver end apparatus, the first compensator is to,

determine a first filter coefficient according to a pilot signal inserted into a transmission signal, and

take the first filter coefficient and/or a parameter obtained through a calculation according to the first filter coefficient as the parameter of the impairment of the receiver end apparatus; and

when determining the parameter of the impairment of the transmitter end apparatus, the second compensator is to,

determine a second filter coefficient according to a pilot signal inserted into a transmission signal, and

take the second filter coefficient and/or a parameter obtained through a calculation according to the second filter coefficient as the parameter of the impairment of the transmitter end apparatus.

6. The system according to claim 5, wherein,

when the first compensator compensates for the impairment of the receiver end apparatus in the received signal according to the parameter of the impairment of the receiver end apparatus, the first compensator is a quasi-static compensator;

and

when the second compensator compensates for the impairment of the transmitter end apparatus in the received signal according to the parameter of the impairment of the transmitter end apparatus, the second compensator is a quasi-static compensator.

7. The system according to claim 5, wherein,

the system includes an impairment monitoring apparatus, and

the first compensator determines the parameter of the impairment of the receiver end according to a parameter of the impairment of the receiver end apparatus determined by the impairment monitoring apparatus;

and

the second compensator determines the parameter of the impairment of the transmitter end apparatus according to a parameter of the impairment of the transmitter end determined by the impairment monitoring apparatus.

8. A method, comprising:

determining a parameter of an impairment in communication performance of the receiver end apparatus by a first monitor according to a set period or a set condition, and

transmitting the parameter of the impairment of the receiver end apparatus to a first compensator to compensate for the impairment of the receiver end apparatus in a received signal, and/or

transmitting the parameter of the impairment of the receiver end apparatus to a management device to cause the management device analyze a cause of the impairment and/or calibrate the receiver end apparatus according to the parameter of the impairment of the receiver end apparatus; and

/or

determining a parameter of an impairment in communication performance of a transmitter end apparatus by a second monitor according to a set period or a set condition, and

transmitting the parameter of the impairment of the transmitter end apparatus to a second compensator to compensate for the impairment of the transmitter end apparatus in the received signal, and/or

transmitting the parameter of the impairment of the transmitter end apparatus to the management device to cause the management device analyze a cause of the impairment and/or calibrate the transmitter end apparatus according to the parameter of the impairment of the transmitter end apparatus,

wherein,

the determining the parameter of the impairment of the receiver end apparatus includes,

determining a first filter coefficient of the first monitor according to a pilot signal inserted into a transmission signal, and

taking the first filter coefficient and/or a parameter obtained through a calculation according to the first filter coefficient as the parameter of the impairment of the receiver end apparatus; and

the determining the parameter of the impairment of the transmitter end apparatus includes,

determining a second filter coefficient of the second monitor according to a pilot signal inserted into a transmission signal, and

taking the second filter coefficient and/or a parameter obtained through a calculation according to the second filter coefficient as the parameter of the impairment of the transmitter end apparatus.