Method and radio node for controlling radio transmission

Patent metadata

Field	Value
Publication number	US-10103775-B2
Application number	US-201415313164-A
Country	US
Kind code	B2
Filing date	May 27, 2014
Priority date	May 27, 2014
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

A method and radio node for controlling transmission of radio signals in a transmitter band to avoid or reduce interference in a victim band, the victim band being separate from the transmitter band in frequency domain. The radio node applies Digital Pre-Distortion, DPD, on signals to be transmitted on at least one carrier in the transmitter band, such that Intermodulation Distortion, IMD, components of the signals are pre-distorted asymmetrically relative the at least one carrier to suppress at least one of the IMD components falling within the victim band. The pre-distorted signals are then amplified in a power amplifier and transmitted on the at least one carrier.

First claim

The invention claimed is:

1. A method performed by a radio node when operating in a wireless network, for controlling transmission of radio signals in a transmitter band to avoid or reduce interference in a victim band, the victim band being separate from the transmitter band in frequency domain, the method comprising:
applying Digital Pre-Distortion (DPD) on signals to be transmitted from the radio node on at least one carrier in the transmitter band, such that Intermodulation Distortion (IMD) components of the signals are pre-distorted on another band in the frequency domain that is asymmetrically relative to the at least one carrier to suppress at least one of the IMD components falling within the victim band;
amplifying the pre-distorted signals in a power amplifier; and,
transmitting the amplified signals on the at least one carrier;
wherein the DPD is applied over a DPD correction band comprising the another band in the frequency domain, and wherein a shifting signal (f CIF ) is multiplied with the signals to be transmitted to shift the DPD correction band in frequency domain asymmetrically relative the signals to be transmitted; and,
wherein a frequency of the shifting signal (f CIF ) is selected based on the victim band's location in frequency domain such that the DPD correction band at least partly coincides with the victim band.

2. The method according to claim 1 , wherein the DPD is applied by using a sampling frequency (f s ) which determines the width of the DPD correction band.

3. The method according to claim 2 , wherein the sampling frequency is selected such that at least one of the IMD components is within the DPD correction band.

4. The method according to claim 2 , wherein the sampling frequency is selected such that the victim band is within the DPD correction band.

5. The method according to claim 1 , wherein the radio node adjusts extension of the DPD correction band based on at least one of: frequency of the transmitted signals, frequency of signals received in the victim band, expected power level or amplitude of the IMD components, current transmission power, and current received signal power.

6. The method according to claim 1 , wherein the radio node is a base station or a wireless device.

7. A non-transitory computer-readable medium comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to claim 1 .

8. A radio node capable of operating in a wireless network, the radio node being arranged to control transmission of radio signals in a transmitter band to avoid or reduce interference in a victim band, the victim band being separate from the transmitter band in frequency domain, the radio node comprising means configured to:
apply Digital Pre-Distortion (DPD) on the signals to be transmitted from the radio node on at least one carrier in the transmitter band, such that Intermodulation Distortion (IMD) components of the signals are pre-distorted on another band in the frequency domain that is asymmetrically relative the at least one carrier to suppress at least one of the IMD components falling within the victim band;
amplify the pre-distorted signals in a power amplifier; and,
transmit the amplified signals on the at least one carrier;
wherein the DPD is applied over a DPD correction band comprising the another band in the frequency domain, and wherein a shifting signal (f CIF ) is multiplied with the signals to be transmitted to shift the DPD correction band in frequency domain asymmetrically relative the signals to be transmitted; and,
wherein a frequency of the shifting signal (f CIF ) is selected based on the victim band's location in frequency domain such that the DPD correction band at least partly coincides with the victim band.

9. The radio node according to claim 8 , comprising means configured to apply the DPD by using a sampling frequency (f s ) which determines the width of the DPD correction band.

10. The radio node according to claim 9 , comprising means configured to select the sampling frequency such that at least one of the IMD components is within the DPD correction band.

11. The radio node according to claim 9 , comprising means configured to select the sampling frequency such that the victim band is within the DPD correction band.

12. The radio node according to claim 8 , comprising means configured to adjust extension of the DPD correction band based on at least one of: frequency of the transmitted signals, frequency of signals received in the victim band, expected power level or amplitude of the IMD components, current transmission power, and current received signal power.

13. The radio node according to claim 8 , wherein the radio node is a base station or a wireless device.

Assignees

• Ericsson Telefon Ab L M
• Ericsson Telefon Ab L M

Inventors

• Heinikoski Kauko
• Leinonen Marko E

Classifications

• H04B1/62 Primary

  for providing a predistortion of the signal in the transmitter and corresponding correction in the receiver, e.g. for improving the signal/noise ratio · CPC title

• H04B7/0639

  Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection · CPC title

• H04B10/697

  Arrangements for reducing noise and distortion · CPC title

• H04B1/525

  with means for reducing leakage of transmitter signal into the receiver · CPC title

• H03F1/3247

  using feedback acting on predistortion circuits (H03F1/3264 takes precedence) · CPC title