Joint estimation and compensation method of RF imperfections in LTE uplink system
First Claim
1. A joint estimation and compensation method of RF imperfections in a LTE uplink system, comprising steps:
- establishing a joint signal model with RF imperfections;
according to said joint signal model, undertaking an initial CFO (Carrier Frequency Offset) estimation of a received signal in a time domain so as to estimate CFO parameters and compensate said received signal;
undertaking a joint estimation of direct-current (DC) offset, multipath channel and imbalance signals of said joint signal model of said received signal, compensating said received signal in said time domain, and acquiring imbalance parameters of said imbalance signals;
determining modulation data to acquire an original transmitted signal;
determining whether error vector magnitude converges;
if yes, estimating gain mismatch parameters and phase mismatch parameters of said joint signal model according to said imbalance parameters; and
if no, using a decision-directed symbol to undertake iterative CFO estimation and compensation so as to undertake further estimation and compensation of said Imperfections until said error vector magnitude converges; and
estimating gain mismatch parameters and phase mismatch parameters of said joint signal model according to said imbalance parameters.
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Abstract
A joint estimation and compensation method of RF imperfections in a LIE (Long Term Evolution) uplink system comprises steps: establishing a joint signal model with RF imperfections; according to the joint signal model, undertaking estimation and compensation of CFO, DC offset, multipath channel, IQ imbalance and shaping filter imbalance of a received signal; and using a frequency equalizer to equalize said received signal and determine modulation data. For reducing computational complexity, the present invention further converts the received signal from a time domain to a frequency domain to undertake frequency domain compensation. The present invention can indeed solve the problems of IQ imbalance, filter imbalance, DC offset, multipath channel and CFO and effectively estimate and compensate RF imperfections in the LTE uplink system.
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Citations
20 Claims
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1. A joint estimation and compensation method of RF imperfections in a LTE uplink system, comprising steps:
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establishing a joint signal model with RF imperfections; according to said joint signal model, undertaking an initial CFO (Carrier Frequency Offset) estimation of a received signal in a time domain so as to estimate CFO parameters and compensate said received signal; undertaking a joint estimation of direct-current (DC) offset, multipath channel and imbalance signals of said joint signal model of said received signal, compensating said received signal in said time domain, and acquiring imbalance parameters of said imbalance signals; determining modulation data to acquire an original transmitted signal; determining whether error vector magnitude converges; if yes, estimating gain mismatch parameters and phase mismatch parameters of said joint signal model according to said imbalance parameters; and if no, using a decision-directed symbol to undertake iterative CFO estimation and compensation so as to undertake further estimation and compensation of said Imperfections until said error vector magnitude converges; and
estimating gain mismatch parameters and phase mismatch parameters of said joint signal model according to said imbalance parameters. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
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