US-12621066-B2 - Method and apparatus for evaluating transmission impairments of multiplexing converter

US12621066B2US 12621066 B2US12621066 B2US 12621066B2US-12621066-B2

Abstract

A method and an apparatus for evaluating transmission impairments of a multiplexing converter. According to the method, impairments of a multiplexing converter are equivalent to the equivalent multiplicative noise and the equivalent additive noise, so as to allow evaluation of transmission impairments of the multiplexing converter, thereby to allow evaluation of the performance of a communication system. The multiplexing converter is a multiplexing analog-to-digital converter, or a multiplexing digital-to-analog converter. According to the present application, impairments of a multiplexing converter can be evaluated accurately, the performance evaluation of a communication system using the multiplexing converter is given, without being affected by an amplitude, a modulation format and a transmission rate of an input signal.

Inventors

Xiaofei SU
Tong YE
Zhenning Tao

Assignees

FUJITSU LIMITED

Dates

Publication Date: 20260505
Application Date: 20231010
Priority Date: 20221017

Claims (10)

1 . An apparatus for evaluating transmission impairments of a multiplexing converter, the apparatus comprising: an evaluation unit configured to: measure equivalent multiplicative noise and equivalent additive noise of a multiplexing converter, the multiplexing converter being a multiplexing analog-to-digital converter, or a multiplexing digital-to-analog converter; and evaluate transmission impairments of the multiplexing converter using the equivalent multiplicative noise and the equivalent additive noise.
2 . The apparatus according to claim 1 , wherein the evaluation unit comprises: a measurement unit, configured to measure, at a receiving end, a power of single tone excitation signals with different amplitudes and at least one frequency, transmitted by a transmitting end, and a power of total harmonic distortion and noise; and a fitting unit, configured to linearly fit the power of the single tone excitation signals and the power of total harmonic distortion and noise to obtain a fitting formula, and an intercept of the fitting formula being used as a power of additive noise for measuring the equivalent additive noise and a slope of the fitting formula being used as a variance of multiplicative noise for measuring the equivalent multiplicative noise.
3 . The apparatus according to claim 1 , wherein the evaluation unit comprises: a measurement unit, configured to measure, at a receiving end, a power of a single tone excitation signal with a single amplitude and at least one frequency, transmitted by a transmitting end, a power of total harmonic distortion and noise, a power of an all-zero excitation signal transmitted by the transmitting end being used as a power of additive noise for measuring the equivalent additive noise, and a power obtained by subtracting the power of the all-zero excitation signal from the power of total harmonic distortion and noise and dividing by the power of the single tone excitation signal being used as a variance of multiplicative noise for measuring the equivalent multiplicative noise.
4 . The apparatus according to claim 2 , wherein, the power of the single tone excitation signals and the power of total harmonic distortion and noise are respectively a power measured at one frequency, or an average power measured at multiple single tone excitation signals with different frequencies; and the average power is obtained by equal-weighted or non-equal-weighted averaging of powers measured at the multiple single tone excitation signals with different frequencies.
5 . An apparatus for communication system performance, the apparatus, the apparatus comprising: a measurement unit, configured to measure equivalent multiplicative noise and equivalent additive noise of a communication system, the communication system comprising a multiplexing analog-to-digital converter and a multiplexing digital-to-analog converter; a calculation unit, configured to multiply an input signal of the communication system by the equivalent multiplicative noise, then plus the equivalent additive noise, as an output signal of the communication system; and an estimation unit, configured to estimate performance of the communication system based on the output signal.
6 . The apparatus according to claim 5 , wherein the input signal of the communication system is a signal that has passed through a linear filter.
7 . The apparatus according to claim 5 , wherein the equivalent additive noise is additive white Gaussian noise with a locked power; and the equivalent multiplicative noise is a random Gaussian distribution noise with a locked variance.
8 . The apparatus according to claim 5 , wherein the measurement unit is configured to measure, at a receiving end, a power of single tone excitation signals with different amplitudes and at least one frequency, transmitted by a transmitting end, and a power of total harmonic distortion and noise; wherein the measurement unit comprises: a fitting unit, configured to linearly fit the power of the single tone excitation signals and the power of total harmonic distortion and noise to obtain a fitting formula, an intercept of the fitting formula being used as a power of additive noise for measuring the equivalent additive noise and a slope of the fitting formula being used as a variance of multiplicative noise for measuring the equivalent multiplicative noise.
9 . The apparatus according to claim 5 , wherein the measurement unit is configured to measure, at a receiving end, a power of a single tone excitation signal with a single amplitude and at least one frequency, transmitted by a transmitting end, a power of total harmonic distortion and noise, a power of an all-zero excitation signal transmitted by the transmitting end being used as a power of additive noise for measuring the equivalent additive noise, and a power obtained by subtracting the power of the all-zero excitation signal from the power of total harmonic distortion and noise and dividing by the power of the single tone excitation signal being used as a variance of multiplicative noise for measuring the equivalent multiplicative noise.
10 . The apparatus according to claim 8 , wherein the power of the single tone excitation signal and the power of total harmonic distortion and noise are respectively a power measured at one frequency, or an average power measured at multiple single tone excitation signals with different frequencies; and the average power is obtained by equal-weighted or non-equal-weighted averaging of powers measured at the multiple single tone excitation signals with different frequencies.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is based on and hereby claims priority to Chinese Application No. 202211267247.0, filed Oct. 17, 2022, in the China National Intellectual Property Administration, the disclosure of which is incorporated herein by reference. FIELD The present disclosure relates to the communication field, in particular to a method and an apparatus for evaluating transmission impairments of a multiplexing converter. BACKGROUND In modern large-capacity and ultra-high-speed optical fiber communication systems, high-speed digital-to-analog converters (DAC) and analog-to-digital converters (ADC) are indispensable devices. In order to achieve high-speed conversion between an analog signal and a digital signal, a high-speed DAC and a high-speed ADC often employ a multiplexing structure, such as time interleaving multiplexing or frequency interleaving multiplexing. A distortion mechanism of such high-speed multiplexing DAC and ADC is very complex. Since the performance of the DAC and the ADC is a fundamental limitation to a communication system, evaluating impairments of a high-speed multiplexing DAC and ADC in a communication system becomes very important. It should be noted that the above introduction to the Background is just to facilitate a clear and complete description of the technical solution of the present disclosure, and is elaborated to facilitate the understanding of persons skilled in the art. It cannot be considered that the above technical solutions are known by persons skilled in the art just because these solutions are elaborated in the Background of the present disclosure. SUMMARY According to an aspect of the embodiments of the present disclosure, an apparatus for evaluating transmission impairments of a multiplexing converter is provided. The apparatus may comprise an evaluation unit, configured to measure equivalent multiplicative noise and equivalent additive noise of a multiplexing converter, the multiplexing converter being a multiplexing analog-to-digital converter, or a multiplexing digital-to-analog converter; and evaluate transmission impairments of the multiplexing converter using the equivalent multiplicative noise and the equivalent additive noise. According to an aspect of the embodiments of the present disclosure, a communication system performance evaluation apparatus is provided. The apparatus may comprise a measurement unit, configured to measure equivalent multiplicative noise and equivalent additive noise of a communication system, the communication system comprising a multiplexing analog-to-digital converter and a multiplexing digital-to-analog converter; a calculation unit, configured to multiply an input signal of the communication system by the equivalent multiplicative noise, then plus the equivalent additive noise, as an output signal of the communication system; and an estimation unit, configured to estimate performance of the communication system based on the output signal. The embodiments of the present disclosure have the following advantageous effects: according to the embodiments of the present disclosure, impairments of a multiplexing converter can be evaluated accurately, the performance evaluation of a communication system using the multiplexing converter is given, without being affected by an amplitude, a modulation format and a transmission rate of an input signal. With reference to the following descriptions and drawings, the specific implementations of the present disclosure are disclosed in detail, the ways in which the principle of the present disclosure can be adopted and pointed out. It should be understood that the implementations of the present disclosure are not limited in terms of the scope. Within the scope of the terms of the appended claims, the implementations of the present disclosure include many changes, modifications and equivalents. Features that are described and/or illustrated with respect to one implementation may be used in the same way or in a similar way in one or more other implementations and in combination with or instead of the features of the other implementations. It should be emphasized that the term “comprise/comprising/includes/including” when being used herein specifies the presence of features, integers, steps or components, but does not preclude the presence or addition of one or more other features, integers, steps or components. BRIEF DESCRIPTION OF THE DRAWINGS Elements and features described in one drawing or implementation of the present embodiments of the present disclosure may be combined with elements and features shown in one or more other drawings or implementations. In addition, in the drawings, similar reference numerals represent corresponding components in several figures, and can be used to indicate corresponding components used in more than one implementations. The included drawings are used to provide a further understanding on the embodiments of the present disclosure,