# US 2022/0286153 A1 · Apparatus for processing passive intermodulation products > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0286153 A1 - Document ID: US20220286153A1 - Status: Published application - Kind: A1 - Application number: 17/760,624 - Filed: 2019-09-17 - Published: 2022-09-08 - Earliest claimed: 2019-09-17 - Assignees: Nokia Solutions and Networks Oy - Applicants: Nokia Solutions and Networks Oy - Inventors: Marko FLEISCHER; Helmut HEINZ; Jakub JUCHNIEWICZ; Rene RÖSCHKE; Jan HELLMANN - Web page: https://patentgrep.com/patent/US20220286153A1 ## CPC - H04B 1/1027: {assessing signal quality or detecting noise/interference for the received signal} - H04B 1/123: {using adaptive balancing or compensation means (adaptive filter circuits and algorithms H03H)} - H04B 1/0053: {with common antenna for more than one band} - H04B 1/0057: {using diplexing or multiplexing filters for selecting the desired band} - H04B 1/109: {by improving strong signal performance of the receiver when strong unwanted signals are present at the receiver input} - H04B 1/126: {having multiple inputs, e.g. auxiliary antenna for receiving interfering signal (aerials in general H01Q)} - H04B 1/525: with means for reducing leakage of transmitter signal into the receiver - H04B 17/18: Monitoring during normal operation - H04B 17/21: for calibration; for correcting measurements - H04B 17/345: Interference values ({signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]} H04B17/336) - H04B: TRANSMISSION ## Abstract The present subject matter relates to an apparatus for a communication system. The communication system comprises transmitters being configured to operate in multiple transmission frequency bands. The apparatus comprises means being configured for: capturing a set of over-the-air signals at distinct frequency bands of the multiple transmission frequency bands; aligning in time the set of signals using delays between the set of signals and a received signal at a selected receiver of the communication system; combining the set of aligned signals to generate a composite signal; and estimating an interference signal that is caused by the set of signals at the selected receiver by weighting the composite signal using a set of one or more calibrated parameters for the estimation. ## Claims ### Claim 1 An apparatus for a communication system, the communication system comprising transmitters being configured to operate in multiple transmission frequency bands, the apparatus comprising: at least one processor; and at least one memory including computer program code, the at least one memory and computer program code being configured, with the at least one processor, to cause the apparatus to perform: capturing a set of over-the-air signals at distinct frequency bands of the multiple transmission frequency bands; aligning in time the set of signals using delays between the set of signals and a received signal at a selected receiver of the communication system; and combining the set of aligned signals to generate a composite signal; estimating an interference signal that is caused by the set of signals at the selected receiver by weighting the composite signal using a set of one or more calibrated parameters for the estimation. ### Claim 2 (depends on 1) The apparatus of claim 1, further comprising an antenna system which, in conjunction with the at least one memory, computer program code, and the at least one processor, performs the capturing, the antenna system being configured to be polarized in accordance with polarizations of the transmitters. ### Claim 3 (depends on 2) The apparatus of claim 2, the antenna system comprising a first antenna being polarized in accordance with a first polarization direction for capturing a subset of signals of the set of signals having the first polarization direction, and a second antenna being polarized in accordance with a second polarization direction for capturing a subset of signals of the set of signals having the second polarization direction. ### Claim 4 (depends on 3) The apparatus of claim 3, wherein the antenna system comprises a receiver per antenna of the antenna system. ### Claim 5 (depends on 1) The apparatus of claim 1, the set of signals comprising inter-band and intra-band signals, wherein the at least one memory and computer program code are further configured, with the at least one processor, to cause the apparatus to determine one same delay for intra-band signals of a same frequency band. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the at least one memory and computer program code are further configured, with the at least one processor, to cause the apparatus to perform a cross correlation of each signal of the set of signals with the received signal; and to determine the delays using results of the cross correlation. ### Claim 7 (depends on 6) The apparatus of claim 6, the cross correlation being performed between absolute values of the signal and absolute values of the received signal. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the at least one memory and computer program code are further configured, with the at least one processor, to cause the apparatus to perform: further aligning in time the set of signals using further delays of the set of signals to the selected receiver; combining the further aligned set of signals to generate a further composite signal; weighting the further composite signal using another set of one or more calibrated parameters, thereby estimating another interference signal that is caused by the set of signals at the selected receiver, the other interference signal having a frequency different from a frequency of the interference signal. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein the at least one memory and computer program code are further configured, with the at least one processor, to cause the apparatus to perform a cross correlation of each signal of the set of signals with a received signal at the selected receiver; and determining the delay of the signal using a maximum value of the resulting cross correlation and determining the other delay of the signal using a second maximum value of the resulting cross correlation. ### Claim 10 (depends on 1) The apparatus of claim 1, the calibrated parameters being parameters of a pulse intermodulation, PIM, model, wherein the at least one memory and computer program code are further configured, with the at least one processor to cause the apparatus to perform determining, during a calibration step, values of the calibrated parameters in accordance with a system configuration of the communication system, the determining comprising comparing estimated interference signals with calibration interference signals. ### Claim 11 (depends on 10) The apparatus of claim 10, the system configuration indicating at least one or more sources of a passive intermodulation, PIM. ### Claim 12 (depends on 1) The apparatus of claim 1, wherein the at least one memory and computer program code are further configured, with the at least one processor, to cause the apparatus to correct a received signal at the selected receiver by using the interference signal. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein the at least one memory and computer program code are further configured, with the at least one processor, to cause the apparatus to correct the signal by a subtraction processing of the interference signal from the received signal being. ### Claim 14 (depends on 1) The apparatus of claim 1, wherein the apparatus comprises a frequency division duplex base transceiver station. ### Claim 15 (canceled) ### Claim 16 A method for a communication system, comprising: capturing a set of over-the-air signals at distinct transmission frequency bands of the communication system; aligning in time the set of signals using delays between the set of signals and a received signal at a selected receiver of the communication system; combining the set of aligned signals to generate a composite signal; estimating an interference signal that is caused by the set of signals at the selected receiver by weighting the composite signal using a set of one or more calibrated parameters. ### Claim 17 (depends on 16) The method of claim 16, further comprising repeating the aligning, combining and weighting for another selected receiver of the communication system, thereby estimating an interference signal that is caused by the set of signals at the other selected receiver. ### Claim 18 (depends on 16) The method of claim 16, further comprising repeating the aligning, combining and weighting steps using for the aligning further delays of the set of signals to the selected receiver and using a set of further calibrated parameters for the weighting. ### Claim 19 A computer program embodied on a non-transitory computer-readable medium, said computer program comprising instructions stored thereon for performing at least: aligning in time a set of captured on-the-air signals using delays between the set of signals and a received signal at a selected receiver of a communication system; combining the set of aligned signals to generate a composite signal; estimating an interference signal that is caused by the set of signals at the selected receiver by weighting the composite signal using a set of one or more calibrated parameters.