Method for aligning receiver I/Q in TDD system and receiver-transmitter platform

Abstract

I / Q imbalance calibration method of receiver machine in TDD system and receiving-transmitting machine platform. The said method comprises: enable the communicator in active state, the baseband moduleproduce signals and send to the communicator; enable the receiver machine in active state, receive signals from communicator and send the obtained signal to the baseband module, carry through the I / Qimbalance calibration processing. The invention calibrate the precision of I / Q imbalance of receiver machine to that of communicator according to the characteristic that TDD system receive and transmit same frequency signals and the I / Q accuracy of communicator itself can meet the requirements of I / Q imbalance performance, measure and calibrate I / Q imbalance with the radio-frequency signals the communicator leak on the receiver machine, improves efficiency, reduces requirements to the instrumentation. As this method has extremely high efficiency, thereby it reduces the requirements of system to the integrated circuit (IC) of receiver machine; provide the possibility to reduce the IC cost of the receiver machine.

Description

technical field [0001] The invention relates to signal processing technology and detection technology, in particular to a calibration method for receiver I / Q imbalance in a TDD system and a transceiver platform capable of I / Q self-test. Background technique [0002] In the communication system, both the in-phase component I and the quadrature component Q of the transmission and reception links have more or less phase and amplitude imbalances, and this I / Q imbalance directly leads to the deterioration of the signal quality of the transmission and reception links. . [0003] On the transmitter side, general digital circuits will not cause I / Q imbalance. From DAC to quadrature up-conversion, the consistency of the circuit and the unsatisfactory orthogonality of the mixer have caused the I / Q imbalance of the transmitter. Q is unbalanced. In general, the design of the hardware circuit of the transmitter can ensure that the performance requirements are met: the typical value of ...

AI Technical Summary

Problems solved by technology

The hardware calibration of the I / Q unbalance of the receiver is completed in the transceiver. Generally, one of the I / Q channels is compensated by hardware. When the phase difference between the two quadrature local oscillators of the quadrature mixer is not At 90°, add a phase shifter to one of the channels to compensate, so that the phases of the two channels can reach quadrature; when the amplification and filtering of the I / Q two channels are inconsistent, resulting in unbalanced amplitudes, attenuate the one with the larger amplitude

The disadvantage of this hardware compensation method is that: due to the increase of hardware, the complexity and cost of the system are increased; moreover, the hardware compensation itself brings inconsistency, and the calibration results are difficult to achieve higher accuracy

As we all know, instruments such as signal generators are relatively expensive, which is a relatively large cost expenditure for the production and improvement of the system; and it is time-consuming and labor-intensive to build a platform and test the normal work of the platform, thereby reducing Efficiency in work and production, complicating software calibration methods

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