CN-122027044-A - DC offset calibration method, device, calibration system and storage medium

CN122027044ACN 122027044 ACN122027044 ACN 122027044ACN-122027044-A

Abstract

The embodiment of the application provides a calibration method, a device, a calibration system and a storage medium for direct current offset, which comprise the steps of obtaining a first compensation value, respectively adjusting an I path first compensation value and a Q path first compensation value based on a polynomial fitting algorithm to obtain an adjusted second compensation value, determining a corresponding adjusted local oscillation leakage value based on the second compensation value, and determining whether the second compensation value corresponding to the adjusted local oscillation leakage value is a target compensation value or not according to the adjusted local oscillation leakage value and a preset threshold value, so that the direct current offset of an I/Q digital-to-analog converter can be rapidly and accurately compensated, the local oscillation leakage of a radio frequency transmitter can be remarkably restrained, the hardware cost is reduced, and various scenes can be adapted.

Inventors

LI XIGUANG
LI FENGYANG
ZHANG YUE
ZHANG GONGJIAN

Assignees

昆腾微电子股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260212

Claims (12)

1. A method of calibrating dc offset, the method comprising: Acquiring a first compensation value, wherein the first compensation value comprises an I path first compensation value and a Q path first compensation value; based on a polynomial fitting algorithm, respectively adjusting the first compensation value of the I path and the first compensation value of the Q path to obtain an adjusted second compensation value; determining a corresponding adjusted local oscillator leakage value based on the second compensation value; And determining whether a second compensation value corresponding to the adjusted local oscillation leakage value is a target compensation value according to the adjusted local oscillation leakage value and a preset threshold value.
2. The method for calibrating dc offset according to claim 1, wherein the adjusting the I-path first compensation value based on the polynomial fitting algorithm comprises: under the condition that the Q-channel first compensation value is unchanged, adding and adjusting the I-channel first compensation value according to a first preset compensation step length to obtain an adjusted third compensation value, and determining a first local oscillator leakage value corresponding to the third compensation value; Reducing and adjusting the first compensation value of the I path according to the first preset compensation step length to obtain an adjusted fourth compensation value, and determining a second local oscillator leakage value corresponding to the fourth compensation value; and determining an adjusted I-path second compensation value by adopting a polynomial fitting algorithm based on a first compensation value at a preset compensation point, a preset local oscillation leakage value corresponding to the first compensation value, a third compensation value, the first local oscillation leakage value, a fourth compensation value and the second local oscillation leakage value.
3. The method for calibrating dc offset according to claim 2, wherein the adjusting the Q-way first compensation value based on the polynomial fitting algorithm includes: Under the condition that the first compensation value of the I path is unchanged, adding and adjusting the first compensation value of the Q path according to a second preset compensation step length to obtain an adjusted fifth compensation value, and determining a third local oscillator leakage value corresponding to the fifth compensation value; Reducing and adjusting the first compensation value of the I path according to the second preset compensation step length to obtain an adjusted sixth compensation value, and determining a fourth local oscillator leakage value corresponding to the sixth compensation value; And determining an adjusted Q-channel second compensation value by adopting a polynomial fitting algorithm based on a first compensation value at a preset compensation point, a preset local oscillation leakage value corresponding to the first compensation value, a fifth compensation value, a third local oscillation leakage value, a sixth compensation value and the fourth local oscillation leakage value.
4. The method of calibrating dc offset according to claim 1, wherein the polynomial fitting algorithm comprises at least a parabolic fitting algorithm.
5. A method for calibrating dc offset according to claim 2 or 3, wherein determining whether the second compensation value corresponding to the adjusted local oscillation leakage value is a target compensation value according to the adjusted local oscillation leakage value and a preset threshold value includes: If the adjusted local oscillation leakage value is smaller than the preset threshold value, determining a second compensation value corresponding to the adjusted local oscillation leakage value as a target compensation value.
6. The method according to claim 5, wherein determining whether the second compensation value corresponding to the adjusted local oscillation leakage value is a target compensation value according to the adjusted local oscillation leakage value and a preset threshold value, comprises: and if the adjusted local oscillator leakage value is larger than the preset threshold value, reselecting the test point, and adjusting by adopting a polynomial fitting algorithm.
7. The method of calibrating a dc offset according to claim 1, wherein the obtaining a first compensation value comprises: obtaining a sample chip; measuring an I-path direct current offset compensation value and a Q-path direct current offset compensation value of each sample chip; adopting a statistical distribution algorithm to carry out statistical analysis on the I-path direct current offset compensation value and the Q-path direct current offset compensation value to obtain an I-path first compensation value and a Q-path first compensation value; And determining the I path first compensation value and the Q path first compensation value as the first compensation values.
8. A calibration apparatus for dc offset, the apparatus comprising: the acquisition module is used for acquiring a first compensation value, wherein the first compensation value comprises an I path first compensation value and a Q path first compensation value; The adjusting module is used for respectively adjusting the first compensation value of the I path and the first compensation value of the Q path based on a polynomial fitting algorithm to obtain an adjusted second compensation value; the determining module is used for determining a corresponding adjusted local oscillator leakage value based on the second compensation value; And the judging module is used for determining whether the second compensation value corresponding to the adjusted local oscillation leakage value is a target compensation value according to the adjusted local oscillation leakage value and a preset threshold value.
9. The apparatus of claim 8, wherein the adjustment module is configured to: under the condition that the Q-channel first compensation value is unchanged, adding and adjusting the I-channel first compensation value according to a first preset compensation step length to obtain an adjusted third compensation value, and determining a first local oscillator leakage value corresponding to the third compensation value; Reducing and adjusting the first compensation value of the I path according to the first preset compensation step length to obtain an adjusted fourth compensation value, and determining a second local oscillator leakage value corresponding to the fourth compensation value; and determining an adjusted I-path second compensation value by adopting a polynomial fitting algorithm based on a first compensation value at a preset compensation point, a preset local oscillation leakage value corresponding to the first compensation value, a third compensation value, the first local oscillation leakage value, a fourth compensation value and the second local oscillation leakage value.
10. The apparatus of claim 8, wherein the adjustment module is configured to: Under the condition that the first compensation value of the I path is unchanged, adding and adjusting the first compensation value of the Q path according to a second preset compensation step length to obtain an adjusted fifth compensation value, and determining a third local oscillator leakage value corresponding to the fifth compensation value; Reducing and adjusting the first compensation value of the I path according to the second preset compensation step length to obtain an adjusted sixth compensation value, and determining a fourth local oscillator leakage value corresponding to the sixth compensation value; And determining an adjusted Q-channel second compensation value by adopting a polynomial fitting algorithm based on a first compensation value at a preset compensation point, a preset local oscillation leakage value corresponding to the first compensation value, a fifth compensation value, a third local oscillation leakage value, a sixth compensation value and the fourth local oscillation leakage value.
11. The calibration system is characterized by comprising a test terminal, a chip to be tested and a measurement module, wherein the chip to be tested and the measurement module are respectively connected with the test terminal, the measurement module is used for measuring local oscillator leakage values under different compensation values, and the test terminal is used for executing the DC offset calibration method according to any one of claims 1-7.
12. A computer readable storage medium, wherein a computer program is stored on the computer readable storage medium, wherein the program, when executed by a processor, implements the method of calibrating a dc offset according to any of claims 1-7.

Description

DC offset calibration method, device, calibration system and storage medium Technical Field The present application relates to the field of radio frequency communications technologies, and in particular, to a method and apparatus for calibrating dc offset, a calibration system, and a storage medium. Background In the field of wireless communication, a radio frequency transmitting system is a core architecture for realizing signal transmission and processing, wherein an orthogonal (I/Q) signal processing technology (comprising a main stream architecture of zero intermediate frequency, low intermediate frequency and the like) is widely applied to various communication terminals and base station equipment due to the characteristics of high spectrum utilization rate and excellent hardware integration level. In the signal link of such a system, the radio frequency baseband signal is subjected to signal coding or waveform generation by a modem, then is decomposed into two paths of baseband signals of in-phase (I) and quadrature (Q), and finally is transmitted through modules of a digital-to-analog converter (DAC), a mixer, a radio frequency front end (comprising an amplifier, a filter), an antenna and the like. In a radio frequency transmitter employing direct up-conversion (zero intermediate frequency) or low intermediate frequency architecture, DC Offset (direct current Offset) present in the output signal of the radio frequency DAC or modulator is directly converted into a mono-tone signal at the carrier frequency (local oscillator frequency), i.e. local oscillator leakage, after passing through the up-conversion mixer. Local oscillator leakage index exceeding standard can increase adjacent channel interference and even trigger a transmitting power limiting mechanism of a communication protocol, thereby directly deteriorating system performance. Therefore, direct Current Offset Compensation (DCOC) is a key technical link for guaranteeing stable operation of the radio frequency transmission system. At present, an offset reference, such as an adjustable direct current bias circuit and a special feedback coupling link, is realized by adopting an additional hardware circuit, but the hardware mode increases complexity and cost and cannot adapt to some specific scenes, so that a method for adapting to various scenes has a low cost and can calibrate the direct current offset to support the stable operation of the radio frequency transceiver system in a complex environment. Disclosure of Invention According to the technical scheme, the first compensation value is obtained, the first compensation value of the I path and the first compensation value of the Q path are respectively adjusted based on a polynomial fitting algorithm, the adjusted second compensation value is obtained, the corresponding adjusted local oscillation leakage value is determined based on the second compensation value, whether the corresponding adjusted local oscillation leakage value is met or not is determined according to the adjusted local oscillation leakage value and a preset threshold value, and if the corresponding adjusted local oscillation leakage value is not met, the local oscillation leakage value can be restrained rapidly and accurately according to the local oscillation leakage of a radio frequency transmitter, and if the corresponding local oscillation leakage value is not met, the local oscillation leakage of the radio frequency transmitter can be restrained rapidly and the radio frequency transmitter can be restrained obviously. In a first aspect, some embodiments of the present application provide a method for calibrating dc offset, including: acquiring a first compensation value, wherein the first compensation value at the preset compensation point at least comprises an I path first compensation value and a Q path first compensation value; based on a polynomial fitting algorithm, respectively adjusting the first compensation value of the I path and the first compensation value of the Q path to obtain an adjusted second compensation value; determining a corresponding adjusted local oscillator leakage value based on the second compensation value; And determining whether a second compensation value corresponding to the adjusted local oscillation leakage value is a target compensation value according to the adjusted local oscillation leakage value and a preset threshold value. According to some embodiments of the application, the first compensation value is obtained, a polynomial fitting algorithm is adopted to respectively adjust the first compensation value of the I path and the first compensation value of the Q path, an adjusted second compensation value is obtained, a corresponding adjusted local oscillation leakage value is calculated according to the second compensation value, the local oscillation leakage value is compared with a preset threshold value, whether the local oscillation leakage value meets the requirement is judg