# US 2018/0026686 A1 · Microwave Radio Transmitter and Receiver for Polarization Misalignment Compensation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0026686 A1 - Document ID: US20180026686A1 - Status: Published application - Kind: A1 - Application number: 15/547,552 - Filed: 2015-02-12 - Published: 2018-01-25 - Earliest claimed: 2015-02-12 - Assignees: Telefonaktiebolaget LM Ericsson (publ) - Applicants: Telefonaktiebolaget LM Ericsson (publ) - Inventors: Markus Gerdin; Björn Gävert; Göran Nilsson - Web page: https://patentgrep.com/patent/US20180026686A1 ## CPC - H04B 7/0469: {taking special antenna structures, e.g. cross polarized antennas into account} - H04B 7/002: {Reducing depolarization effects} - H04B 7/10: Polarisation diversity; Directional diversity - H04B 17/12: of transmit antennas, e.g. of the amplitude or phase - H04B: TRANSMISSION ## Abstract This disclosure provides a microwave radio transmitter for radio transmission to a microwave radio receiver. The microwave radio transmitter comprises an antenna arrangement and a baseband processing module connected to the antenna arrangement. The antenna arrangement comprises an antenna having a polarization. The baseband processing module is configured to receive a polarization misalignment indication from the microwave radio receiver. The polarization misalignment indication is indicative of a misalignment between the polarization of the antenna and a corresponding polarization of a receive antenna comprised in the microwave radio receiver. The baseband processing module is configured to compensate for polarization misalignment between the antenna and the receive antenna by adjusting the radio transmission based on the polarization misalignment indication. ## Claims ### Claim at position 1 1-25. (canceled) ### Claim 26 A microwave radio transmitter for radio transmission to a microwave radio receiver, the microwave radio transmitter comprising: an antenna arrangement comprising an antenna having a polarization; a baseband processing circuitry connected to the antenna arrangement, the baseband processing circuitry being configured to: receive a polarization misalignment indication from the microwave radio receiver, the polarization misalignment indication being indicative of a misalignment between the polarization of the antenna and a corresponding polarization of a receive antenna comprised in the microwave radio receiver; and compensate for polarization misalignment between the antenna and the receive antenna by adjusting the radio transmission based on the polarization misalignment indication. ### Claim 27 (depends on 26) The microwave radio transmitter of claim 26, wherein the baseband processing circuitry is further configured to compensate for polarization misalignment by generating an output signal for radio transmission based on an input signal and the received polarization misalignment indication. ### Claim 28 (depends on 26) The microwave radio transmitter of claim 26, wherein the antenna is a first antenna having a first polarization, and wherein the antenna arrangement further comprises a second antenna having a second polarization. ### Claim 29 (depends on 28) The microwave radio transmitter of claim 28, wherein the baseband processing circuitry is configured to receive, from the microwave radio receiver, a polarization misalignment indication indicative of a misalignment between the second polarization and a corresponding polarization of a second receive antenna comprised in the microwave radio receiver. ### Claim 30 (depends on 26) The microwave radio transmitter of claim 26, wherein the antenna arrangement is configured to transmit a signal using the polarization to enable detection of the polarization misalignment at the microwave radio receiver. ### Claim 31 A microwave radio receiver for reception of radio transmission from a microwave radio transmitter, the microwave radio receiver comprising: an antenna arrangement comprising an antenna having a polarization; a baseband processing circuitry connected to the antenna arrangement; wherein the antenna is configured to receive a signal from the microwave radio transmitter; wherein the baseband processing circuitry is configured to determine a polarization misalignment indication based on the received signal, the polarization misalignment indication being indicative of a misalignment between the polarization of the antenna and a corresponding polarization of a transmit antenna comprised in the microwave radio transmitter; and wherein the antenna arrangement is configured to transmit the polarization misalignment indication to the microwave radio transmitter. ### Claim 32 (depends on 31) The microwave radio receiver of claim 31, wherein the baseband processing circuitry is configured to compensate for polarization misalignment between the polarization of the antenna and the corresponding polarization of the transmit antenna comprised in the microwave radio transmitter by adjusting the received signal based on the polarization misalignment indication. ### Claim 33 (depends on 31) The microwave radio receiver of claim 31: wherein the antenna is a first antenna having a first polarization and configured to receive a first signal from the microwave radio transmitter; wherein the antenna arrangement comprises a second antenna having a second polarization and configured to receive a second signal from the microwave radio transmitter. ### Claim 34 (depends on 33) The microwave radio receiver of claim 33, wherein the baseband processing circuitry is configured to: measure a received power on the second polarization for the first signal received by the first polarization; and determine the polarization misalignment indication based on the measured received power. ### Claim 35 (depends on 33) The microwave radio receiver of claim 33: wherein the antenna arrangement is configured to receive the first signal on the first polarization and the second signal on the second polarization; and wherein the baseband processing circuitry is configured to: estimate a cross-correlation between the first signal and the second signal; and determine the polarization misalignment indication based on the estimated cross-correlation. ### Claim 36 (depends on 31) The microwave radio receiver of claim 31, wherein the baseband processing circuitry is configured to iteratively determine the polarization misalignment indication and to compensate for the misalignment. ### Claim 37 A network node, comprising: a microwave radio transmitter for radio transmission to a microwave radio receiver, the microwave radio transmitter comprising: an antenna arrangement comprising an antenna having a polarization; a baseband processing circuitry connected to the antenna arrangement, the baseband processing circuitry being configured to: receive a polarization misalignment indication from the microwave radio receiver, the polarization misalignment indication being indicative of a misalignment between the polarization of the antenna and a corresponding polarization of a receive antenna comprised in the microwave radio receiver; and compensate for polarization misalignment between the antenna and the receive antenna by adjusting the radio transmission based on the polarization misalignment indication. ### Claim 38 A network node, comprising: a microwave radio receiver for reception of radio transmission from a microwave radio transmitter, the microwave radio receiver comprising: an antenna arrangement comprising an antenna having a polarization; a baseband processing circuitry connected to the antenna arrangement; wherein the antenna is configured to receive a signal from the microwave radio transmitter; wherein the baseband processing circuitry is configured to determine a polarization misalignment indication based on the received signal, the polarization misalignment indication being indicative of a misalignment between the polarization of the antenna and a corresponding polarization of a transmit antenna comprised in the microwave radio transmitter; and wherein the antenna arrangement is configured to transmit the polarization misalignment indication to the microwave radio transmitter ### Claim 39 A method, performed in a microwave radio transmitter, for radio transmissions to a microwave radio receiver, the microwave radio transmitter comprising an antenna arrangement and a baseband processing circuitry connected to the antenna arrangement, the antenna arrangement comprising an antenna having a polarization; the method comprising: receiving a polarization misalignment indication from the microwave radio receiver, the polarization misalignment indication being indicative of a misalignment between the polarization and a corresponding polarization of a receive antenna comprised in the microwave radio receiver; and compensating for polarization misalignment between the antenna and the receive antenna by adjusting the radio transmission based on the polarization misalignment indication. ### Claim 40 (depends on 39) The method of claim 39, wherein the adjusting comprises generating an output signal based on an input signal and the received polarization misalignment indication. ### Claim 41 (depends on 39) The method of claim 39: wherein the antenna is a first antenna having a first polarization; wherein the antenna arrangement comprises a second antenna having a second polarization; wherein the receiving comprises receiving from the microwave radio receiver a polarization misalignment indication indicative of a misalignment between the second polarization and a corresponding polarization of a second receive antenna comprised in the microwave radio receiver. ### Claim 42 (depends on 39) The method of claim 39, further comprising transmitting a signal using at least one polarization to enable detection of the misalignment at the microwave radio receiver. ### Claim 43 A method, performed in a microwave radio receiver, for reception of radio transmission from a microwave radio transmitter, the microwave radio receiver comprising an antenna arrangement and a baseband processing circuitry connected to the antenna arrangement, the antenna arrangement comprising an antenna having a polarization, the method comprising: receiving a signal from a microwave radio transmitter on the antenna; determining a polarization misalignment indication based on the received signal, the polarization misalignment indication being indicative of a misalignment between the polarization and a corresponding polarization of a transmit antenna comprised in the microwave radio transmitter; and transmitting the polarization misalignment indication to the microwave radio transmitter. ### Claim 44 (depends on 43) The method of claim 43, further comprising compensating for polarization misalignment between the antenna and the transmit antenna by adjusting the received signal based on the polarization misalignment indication. ### Claim 45 (depends on 44) The method of claim 44, wherein the adjusting comprises processing the received signal using the polarization misalignment indication. ### Claim 46 (depends on 43) The method of claim 43: wherein the antenna is a first antenna having a first polarization and configured to receive a first signal from the microwave radio transmitter; wherein the antenna arrangement comprises a second antenna having a second polarization and configured to receive a second signal from the microwave radio transmitter; wherein the determining comprises: measuring a received power on the second polarization for the first signal received on the first polarization; and determining the polarization misalignment indication based on the measured received power. ### Claim 47 (depends on 43) The method of claim 43: wherein the antenna is a first antenna having a first polarization and configured to receive a first signal from the microwave radio transmitter; wherein the antenna arrangement comprises a second antenna having a second polarization and configured to receive a second signal from the microwave radio transmitter; wherein the determining comprises: receiving the second signal on the second polarization; estimating a cross-correlation between the first signal and the second signal; and determining the polarization misalignment indication based on the estimated cross-correlation. ### Claim 48 (depends on 44) The method of claim 44, wherein the determining and the compensating are performed iteratively. ### Claim 49 A non-transitory computer readable recording medium storing a computer program product for controlling radio transmissions from a microwave radio transmitter to a microwave radio receiver, the microwave radio transmitter comprising an antenna arrangement and a baseband processing circuitry connected to the antenna arrangement, the antenna arrangement comprising an antenna having a polarization; the computer program product comprising software instructions which, when run on the processing circuitry, causes the microwave radio transmitter to: receive a polarization misalignment indication from the microwave radio receiver, the polarization misalignment indication being indicative of a misalignment between the polarization and a corresponding polarization of a receive antenna comprised in the microwave radio receiver; and compensate for polarization misalignment between the antenna and the receive antenna by adjusting the radio transmission based on the polarization misalignment indication. ### Claim 50 A non-transitory computer readable recording medium storing a computer program product for controlling reception of radio transmission from a microwave radio transmitter to a microwave radio receiver, the microwave radio receiver comprising an antenna arrangement and a baseband processing circuitry connected to the antenna arrangement, the antenna arrangement comprising an antenna having a polarization, the computer program product comprising software instructions which, when run on the processing circuitry, causes the microwave radio receiver to: receive a signal from a microwave radio transmitter on the antenna; determine a polarization misalignment indication based on the received signal, the polarization misalignment indication being indicative of a misalignment between the polarization and a corresponding polarization of a transmit antenna comprised in the microwave radio transmitter; and transmit the polarization misalignment indication to the microwave radio transmitter.