Local oscillation leakage detection and elimination apparatus and method

Abstract

The present invention provides a local oscillator leakage detection and elimination device. The device comprises a frequency conversion and analog-to-digital conversion unit for performing frequency conversion for signals to be sent and converting the converted analog signals to digital signals; a digital filter unit for filtering converted digital signals and filtering out useful signals and mixed signals comprising user signals and local oscillator leakage signals; a power detection unit for performing power detection to mixed signals and useful signals and calculating the power of local oscillator leakage signals; a control unit for controlling the operation of calibration circuit according to the obtained power value of the local oscillator leakage signals to make the calibration circuit eliminate generated local oscillator leakage signals.

Description

technical field [0001] The invention relates to a local oscillator leakage detection and elimination device and method in a transmitter, in particular, it relates to detecting the power of a local oscillator leakage signal in the digital domain, which can realize high detection accuracy, large dynamic range, and good real-time performance. The invention discloses a device and method for detecting and eliminating vibration and leakage, and reduces useless signals generated by frequency converters. Background technique [0002] In the field of wireless communication, a traditional transmitter consists of a baseband unit, an analog-to-digital conversion unit, a frequency conversion unit, an amplification unit, and a filter unit. Among them, the transmitter completes the shift of the signal spectrum through the frequency converter. In the process of frequency conversion, some non-useful signals will inevitably be generated, such as local oscillator leakage signals, other sideba...

AI Technical Summary

Problems solved by technology

[0004] The existing local oscillator leakage detection circuit mainly uses the form of analog circuit to detect the local oscillator leakage signal. This detection method usually has the disadvantages of low precision and large error.

Especially, in the case of a transmitter structure, that is, the normal working state of the zero-IF transmitter, since the useful signal of the user and the leakage signal of the local oscillator are in the same frequency band, the detection circuit based on the traditional analog circuit cannot accurately Detects the power of the LO leakage signal

Therefore, in this kind of transmitter, the local oscillator leakage cannot be calibrated in real time, and can only be calibrated at power-on or when there is no useful user signal

Images