# US 2010/0166109 A1 · Radio station and active antenna array > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2010/0166109 A1 - Document ID: US20100166109A1 - Status: Published application - Kind: A1 - Application number: 12/648,000 - Filed: 2009-12-28 - Published: 2010-07-01 - Earliest claimed: 2008-12-31 - Assignees: Ubidyne, Inc. - Inventors: Dirk Neumann; Peter Kenington - Web page: https://patentgrep.com/patent/US20100166109A1 ## CPC - H03F 1/3247: {using feedback acting on predistortion circuits (H03F1/3264 takes precedence)} - H03F 1/3258: {based on polynomial terms} - H03F 1/3294: {Acting on the real and imaginary components of the input signal} - H03F 3/24: of transmitter output stages - H03F 3/68: Combinations of amplifiers, e.g. multi-channel amplifiers for stereophonics {(power amplifiers using a combination of several semiconductor amplifiers H03F3/211; combinations of amplifiers using coupling networks with distributed constants H03F3/602)} - H04L 27/368: {adaptive predistortion} - H03F 2200/204: A hybrid coupler being used at the output of an amplifier circuit - H03F 2200/207: A hybrid coupler being used as power measuring circuit at the output of an amplifier circuit - H03F 2200/336: A I/Q, i.e. phase quadrature, modulator or demodulator being used in an amplifying circuit - H03F 2200/451: the amplifier being a radio frequency amplifier - H03F 2201/3233: Adaptive predistortion using lookup table, e.g. memory, RAM, ROM, LUT, to generate the predistortion - H03F: AMPLIFIERS - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract The present disclosure relates to a radio station providing a digital predistortion to be imposed on a payload signal. The digital predistortion is usable as a general predistortion for several transmit paths of the radio station. The radio station provides coupled transmit signals to be combined within a combiner forming a common feedback signal. The common feedback signal is relayed along a common feedback path. A digital predistortion update unit to updates the digital predistortion in order to linearise a transfer characteristics of the transmit paths. The disclosure relates to a method of digitally predistorting a payload signal in order to linearise a transmit characteristics of the transmit paths. The disclosure further relates to computer program products for the manufacture of the radio station and/or a computer product for the execution of the method digitally predistorting. The disclosure further relates to an antenna array comprising the radio station. ## Claims ### Claim 1 A radio station comprising: a digital predistortion module adapted to impose a digital predistortion on a payload signal, at least one transmit path adapted to relay the payload signal as a transmit signal, an RF amplifier within the at least one transmit path adapted to amplify the payload signal, an antenna element or sub-array terminating the at least one transmit path, a coupler adapted to extract at least one coupled transmit signal out of the transmit signal, a combiner adapted to combine the at least one coupled transmit signal into a common feedback signal; a common feedback path adapted to feed the common feedback signal to a digital predistortion update module adapted to update the digital predistortion; thus linearising transfer characteristics of at least one of the at least one transmit paths. ### Claim 2 (depends on 1) The radio station according to claim 1, wherein the predistortion module comprises a digital signal processor. ### Claim 3 (depends on 1) The radio station according to claim 1, further comprising an input stage adapted to accept the payload signal. ### Claim 4 (depends on 1) The radio station according to claim 1, wherein the at least one transmit path comprises a digital-to-analogue converter. ### Claim 5 (depends on 4) The radio station according to claim 4, wherein the digital-to-analogue-converter comprises a delta-sigma digital-to-analogue converter. ### Claim 6 (depends on 1) The radio station according to claim 1, wherein the at least one transmit path further comprises a band pass filter. ### Claim 7 (depends on 1) The radio station according to claim 1, wherein the common feedback path comprises an attenuator. ### Claim 8 (depends on 1) The radio station according to claim 1, further comprising at least one attenuator upstream of the combiner. ### Claim 9 (depends on 1) The radio station according to claim 1, wherein the common feedback path further comprises an analog-to-digital converter adapted to digitize the common feedback signal. ### Claim 10 (depends on 9) The radio station according to claim 9, wherein the analogue-to-digital converter comprises a delta-sigma analogue-to-digital converter. ### Claim 11 A method for digitally predistorting a payload signal, the method comprising: providing the payload signal to be relayed as a transmit signal along at least one transmit path, imposing a digital predistortion on the payload signal, extracting at least one coupled transmit signal out of the transmit signal, combining at least one of the at least one coupled transmit signals, thus forming a common feedback signal, updating the digital predistortion using the common feedback signal; thereby linearising a transfer characteristics of at least one of the transmit paths. ### Claim 12 (depends on 11) The method according to claim 11, further comprising: analogue-to-digital converting the transmit signal. ### Claim 13 (depends on 12) The method according to claim 12, wherein the converting comprises: digital-to-analogue converting using a delta-sigma converter. ### Claim 14 (depends on 12) The method according to claim 12, wherein the converting further comprises: digital-to-analogueconverting using an analogue-to-digital converter, upconverting the transmit signal. ### Claim 15 (depends on 11) The method according claim 11, further comprising: amplifying the transmit signal. ### Claim 16 (depends on 11) The method according claim 11, further comprising: filtering the transmit signal. ### Claim 17 (depends on 11) The method according claim 11, further comprising: attenuating the common feedback signal. ### Claim 18 (depends on 11) The method according claim 11, further comprising: attenuating at least one of the at least one coupled transmit signal. ### Claim 19 (depends on 11) The method according claim 11, further comprising: analogue-to-digital converting the common feedback signal. ### Claim 20 (depends on 11) The method according claim 11, wherein the updating comprises: delaying the payload signal thus forming a delayed payload signal. ### Claim 21 (depends on 11) The method according claim 11, wherein the updating comprises averaging the common feedback signal, extracting of differences between the common feedback signal and at least one of the payload signal or the delayed payload signal. ### Claim 22 Computer program product embodied on a computer-readable medium and comprising executable instructions for the manufacture of a radio station, the radio station comprising: a digital predistortion module adapted to impose a digital predistortion on a payload signal, at least one transmit path adapted to relay the payload signal as a transmit signal, an RF amplifier within the at least one transmit path adapted to amplify the payload signal, an antenna element or sub-array terminating the at least one transmit path, a coupler adapted to extract at least one coupled transmit signal out of the transmit signal, a combiner adapted to combine the at least one coupled transmit signal into a common feedback signal; a common feedback path adapted to feed the common feedback signal to a digital predistortion update module adapted to update the digital predistortion; thus linearising transfer characteristics of at least one of the at least one transmit paths. ### Claim 23 Computer program product comprising instructions that enable a processor to carry out a method for digitally predistorting a payload signal, the method comprising: providing the payload signal to be relayed as a transmit signal along at least one transmit path, imposing a digital predistortion on the payload signal, extracting at least one coupled transmit signal out of the transmit signal, combining at least one of the at least one coupled transmit signals, thus forming a common feedback signal, updating the digital predistortion using the common feedback signal; thereby linearising a transfer characteristics of at least one of the transmit paths. ### Claim 24 An active antenna array comprising: a radio station (1) comprising: a digital predistortion module adapted to impose a digital predistortion on a payload signal, at least one transmit path adapted to relay the payload signal as a transmit signal, an RF amplifier within the at least one transmit path adapted to amplify the payload signal, an antenna element or sub-array terminating the at least one transmit path, a coupler adapted to extract at least one coupled transmit signal out of the transmit signal, a combiner adapted to combine the at least one coupled transmit signal into a common feedback signal; a common feedback path adapted to feed the common feedback signal to a digital predistortion update module adapted to update the digital predistortion; thus linearising transfer characteristics of at least one of the at least one transmit paths; wherein the antenna element or sub-array comprises an adjustable phase and magnitude between individual ones of the antenna elements or sub-arrays; and a signal conditioner adapted to impose phase and magnitude differences between the antenna elements. ### Claim 25 (depends on 24) The active antenna array according to claim 24, further comprising at least one receive path terminated by the antenna element, wherein the at least one receive path is adapted to receive a receive signal. ### Claim 26 (depends on 24) The active antenna array according claim 24, wherein the phase and magnitude difference comprises a transmit phase and magnitude difference accumulated along the at least one transmit path for at least one of the at least one transmit paths. ### Claim 27 (depends on 24) The active antenna array according claim 24, wherein the phase and magnitude difference comprises a receive phase and magnitude difference accumulated along the at least one receive path for at least one of the at least one receive paths. ### Claim 28 (depends on 24) The active antenna array according claim 24, wherein the signal conditioner comprises a digital signal processor. ### Claim 29 (depends on 24) The active antenna array according claim 24, wherein the signal conditioner comprises the digital signal processor of the radio station. ### Claim 30 (depends on 24) The active antenna array according claim 24, wherein the signal conditioner is further adapted to derive the transmit magnitude and phase deviations. ### Claim 31 (depends on 24) The active antenna array according claim 24, wherein the signal conditioner is further adapted to derive the receive magnitude and phase deviation. ### Claim 32 (depends on 24) The active antenna array according claim 24, wherein the signal conditioner is adapted to impose phase and magnitude changes on at least two of the transmit paths, such that the transmission of the active antenna array substantially comprises a defined phase and magnitude relation between at least one pair of the antenna elements. ### Claim 33 (depends on 24) The active antenna array according claim 24, wherein the signal conditioner is adapted to impose phase and magnitude changes on at least two of the of the at least one receive paths, such that the reception of the active antenna array substantially comprises a defined phase and magnitude relation between at least one pair of the receive signals. ### Claim 34 (depends on 24) The active antenna array according claim 24, wherein the transmission of the active antenna array is substantially coherent between at least one pair of the antenna elements. ### Claim 35 (depends on 24) The active antenna array according claim 24, wherein the active antenna array is adapted to provide at least one of beam forming, down tilting, beam diversity and direction of arrival detection. ### Claim 36 A radio station comprising: a digital predistortion module adapted to impose a digital predistortion on a payload signal, at least one transmit path adapted to relay the payload signal as a transmit signal, an RF amplifier within the at least one transmit path adapted to amplify the payload signal, a coupler adapted to extract at least one coupled transmit signal out of the transmit signal, a combiner adapted to combine the at least one coupled transmit signal into a common feedback signal; a common feedback path adapted to feed the common feedback signal to a digital predistortion update module adapted to update the digital predistortion; thus linearising transfer characteristics of at least one of the at least one transmit paths.