Method and apparatus for reduced intermodulation distortion in a radio transceiver
AssigneeTelefonaktiebolaget LM Ericsson (publ)
InventorsUwe Hildebrand, Thomas Unshelm
Life of this patent
Estimating the term…
Abstract
A transceiver transmits first and second signals on first and second transmit radio frequencies. After detecting a received signal, intermodulation distortion caused by transmission of the first and second signals is suppressed, reduced, and/or eliminated using information associated with the first and second transmitted signals. More specifically, the information associated with the first and second transmitted signals is used to calculate or otherwise obtain a correction factor that corresponds to the intermodulation distortion. The correction factor is subtracted from the received signal to suppress the intermodulation distortion.
Claims45
Apparatus comprising:
- one or more transmitters for transmitting first and second transmissions on first and second radio frequencies, respectively, where the first and second transmissions result in intermodulation distortion in a receive radio frequency band, and
- a compensator for compensating the intermodulation distortion using information associated with the first and second transmissions,
- wherein the compensator includes:
- a correction calculator for generating a correction factor that corresponds to the intermodulation distortion, and
- a subtractor for subtracting the correction factor from a signal received in the receive radio frequency band thereby suppressing the intermodulation distortion in the received signal,
- wherein the correction calculator is configured to generate the correction factor using first and second baseband data contained in the first and second radio transmissions, respectively, and
- wherein the correction calculator includes a synchronizer for synchronizing when the first and second baseband data are supplied to the correction calculator.
A receiver for receiving signals in a receive radio frequency band that includes intermodulation distortion caused by transmission of first and second signals on first and second radio frequencies by a transmitter, comprising:
- radio receiving circuitry for receiving a received signal in the receive radio frequency band, and
- processing circuitry configured to compensate for the intermodulation distortion present in the received signal using information associated with the first and second signals provided by the transmitter,
- wherein the processing circuitry includes a calculator for generating a compensation signal using the information associated with the first and second signals and a combiner for reducing or removing the intermodulation distortion present in the received signal using the compensation signals, and
- a synchronizer for synchronizing a time when the compensation signal is combined with the received signal.
A receiver for receiving signals in a receive radio frequency band that includes intermodulation distortion caused by transmission of first and second baseband signals on first and second radio frequencies by a transmitter, comprising:
- radio receiving circuitry for receiving a received signal in the receive radio frequency band, and
- processing circuitry configured to compensate for the intermodulation distortion present in the received signal using information associated with the first and second baseband signals provided by the transmitter including a calculator for generating a compensation signal using the information associated with the first and second signals,
- a synchronizer for synchronizing when the first and second baseband data are supplied to the calculator.
A method for compensating for intermodulation distortion in a received signal caused by transmission of first and second signals on first and second radio frequencies, comprising:
- detecting the received signal,
- suppressing the intermodulation distortion in the received signal using information associated with the first and second signals including generating a correction factor that corresponds to the intermodulation distortion,
- subtracting the correction factor from the received signal, and
- synchronizing when the correction factor is subtracted from the received signal.
Apparatus for compensating for intermodulation distortion in a received signal caused by transmission of first and second signals on first and second radio frequencies, comprising:
- means for detecting the received signal;
- means for suppressing the intermodulation distortion in the received signal using information associated with the first and second signals including:
- means for generating a correction factor that corresponds to the intermodulation distortion, and
- means for subtracting the correction factor from the received signal, and
- wherein the means for generating generates the correction factor in accordance with the following equation:
- a3=α*(a1+a2)+β*(a1+a2)2+γ*(a1+a2)3
- where a3 is the correction factor, a1 and a2 are first and second baseband signals, and α, β, and γ are parameters whose values may be adaptively set.
Dependencies are inferred from the claim text.