# US 8,787,862 B2 · Method of receiving and receivers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,787,862 B2 - Document ID: US8787862B2 - Status: Granted - Kind: B2 - Application number: 13/677,866 - Filed: 2012-11-15 - Published: 2013-05-23 - Granted: 2014-07-22 - Earliest claimed: 2011-11-17 - Assignees: Broadcom Corporation - Applicants: Broadcom Corporation - Inventors: Jouni Kristian Kaukovuori; Aarno Tapio Parssinen; Antti Oskari Immonen - Web page: https://patentgrep.com/patent/US8787862B2 ## CPC - H03J 7/04: where the frequency control is accomplished by varying the electrical characteristics of a non-mechanically adjustable element or where the nature of the frequency controlling element is not significant - H03D 3/009: {Compensating quadrature phase or amplitude imbalances} - H03J: TUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS - H03D: DEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER (masers, lasers H01S; circuits capable of acting both as modulator and demodulator H03C; details applicable to both modulators and frequency-changers H03C; demodulating pulses H03K9/00; transforming types of pulse modulation H03K11/00; coding, decoding or code conversion, in general H03M; repeater stations H04B7/14; demodulators adapted for AC systems of digital information transmission H04L27/00; synchronous demodulators adapted for colour television H04N9/66) ## Abstract A receiver uses a local oscillator to receive data transmitted via a combination of radio frequency signals using carrier aggregation. Each radio frequency signal occupies a respective radio frequency band and the radio frequency bands are arranged in two groups, a first group and a second group, separated in frequency by a first frequency region, each of the groups including one or more radio frequency bands and the first group occupying a wider frequency region than the second group. The radio frequency signals are processed using the local oscillator by setting the local oscillator, during the processing, to a frequency that is offset from the center of a band defined by outer edges of the frequency regions occupied by the two groups. ## Claims ### Claim 1 A method of receiving data transmitted via a combination of a plurality of radio frequency signals using carrier aggregation, the method comprising: processing at least said plurality of radio frequency signals using a local oscillator, each radio frequency signal occupying a respective band of a plurality of radio frequency bands, the plurality of radio frequency bands being arranged in two groups, a first group and a second group, separated in frequency by a first frequency region, each of the groups including one or more radio frequency bands and the first group occupying a wider frequency region than the second group; and setting said local oscillator, during said processing, to a frequency that is offset from the centre of a band defined by outer edges of the frequency regions occupied by the two groups, wherein the frequency to which the local oscillator is set is within one quarter of the bandwidth of one of the plurality of radio frequency bands from a frequency mid-way between the centre of the frequency region occupied by the first group and the centre of the frequency region occupied by the second group. ### Claim 2 (depends on 1) The method according to claim 1, wherein the frequency to which the local oscillator is set is within one eighth of the bandwidth of one of the plurality of radio frequency bands from a frequency mid-way between the centre of the frequency region occupied by the first group and the centre of the frequency region occupied by the second group. ### Claim 3 (depends on 1) The method according to claim 1, wherein the first frequency region is not used for transmitting said data. ### Claim 4 (depends on 1) The method according to claim 1, wherein the first frequency region comprises a radio frequency band occupied by a radio frequency signal that is not aggregated with said plurality of radio frequency signals. ### Claim 5 (depends on 1) The method according to claim 1, wherein at least one of the groups includes non-contiguous radio frequency bands. ### Claim 6 (depends on 1) The method according to claim 1, wherein the frequency to which the local oscillator is set is substantially mid-way between the centre of the frequency region occupied by the first group and the centre of the frequency region occupied by the second group. ### Claim 7 (depends on 1) The method according to claim 1, the method further comprising: determining the offset in dependence on a measurement of signal quality of at least one of the plurality of radio frequency signals. ### Claim 8 (depends on 7) The method according to claim 7, further comprising: receiving a first subset of the downconverted plurality of radio frequency signals using the first bandpass filtered inphase and quadrature components and receiving a second subset of the downconverted plurality of radio frequency signals using the second bandpass filtered inphase and quadrature components, wherein: the first subset of the downconverted plurality radio frequency signals are downconverted from radio frequency bands in the first group; and the second subset of the downconverted plurality radio frequency signals are downconverted from radio frequency bands in the second group. ### Claim 9 (depends on 1) The method according to claim 1, wherein said processing comprises: downconverting said plurality of radio frequency signals using quadrature mixing to give inphase and quadrature components; filtering said inphase and quadrature components using a first bandpass filter bandwidth to give first bandpass filtered inphase and quadrature components; and filtering said inphase and quadrature components using a second bandpass filter bandwidth, different from the first bandpass filter bandwidth, to give second bandpass filtered inphase and quadrature components. ### Claim 10 (depends on 9) The method according to claim 9, the method further comprising using a complex filter to perform at least one of the steps of: filtering said inphase and quadrature components to give first bandpass filtered inphase and quadrature components using a first complex filter; and filtering said inphase and quadrature components to give second bandpass filtered inphase and quadrature components using a second complex filter. ### Claim 11 A receiver for receiving data transmitted via a combination of a plurality of radio frequency signals using carrier aggregation, wherein each radio frequency signal occupies a respective band of a plurality of radio frequency bands, the plurality of radio frequency bands being arranged in two groups separated in frequency by a first frequency region, the first of the two groups occupying a wider frequency region than the second group, the receiver comprising: a controller configured to determine a frequency that is offset from the centre of a band defined by outer edges of the frequency regions occupied by the two groups; and a signal processor for processing said plurality of radio frequency signals using a local oscillator set to the determined frequency. ### Claim 12 (depends on 11) The receiver according to claim 11, wherein the first frequency region is not used for transmitting said data. ### Claim 13 (depends on 11) The receiver according to claim 11, wherein the first frequency region comprises a radio frequency band occupied by a radio frequency signal that is not aggregated with said plurality of radio frequency signals. ### Claim 14 (depends on 11) The receiver according to claim 11, wherein the controller is configured to determine a frequency within one quarter of the bandwidth of one of the plurality of radio frequency bands from a frequency mid-way between the centre of the frequency region occupied by the first group and the centre of the frequency region occupied by the second group. ### Claim 15 (depends on 14) The receiver according to claim 14, wherein the controller is configured to determine a frequency substantially mid-way between the centre of the frequency region occupied by the first group and the centre of the frequency region occupied by the second group. ### Claim 16 (depends on 11) The receiver according to claim 11, wherein the controller is configured to determine a frequency within one eighth of the bandwidth of one of the plurality of radio frequency bands from a frequency mid-way between the centre of the frequency region occupied by the first group and the centre of the frequency region occupied by the second group. ### Claim 17 (depends on 11) The receiver according to claim 11, wherein the controller is configured to determine the offset in dependence on a measurement of signal quality of at least one of the plurality of radio frequency signals. ### Claim 18 (depends on 11) The receiver according to claim 11, wherein said signal processor is configured to: downconvert said plurality of radio frequency signals using quadrature mixing to give inphase and quadrature components; filter said inphase and quadrature components using a first bandpass filter bandwidth to give first bandpass filtered inphase and quadrature components; and filter said inphase and quadrature components using a second bandpass filter bandwidth, different from the first bandpass filter bandwidth, to give second bandpass filtered inphase and quadrature components. ### Claim 19 (depends on 18) The receiver according to claim 18, the receiver comprising at least one of: a first complex filter configured to perform said filtering of said inphase and quadrature components to give first bandpass filtered inphase and quadrature components; and a second complex filter configured to perform said filtering of said inphase and quadrature components to give second bandpass filtered inphase and quadrature components. ### Claim 20 (depends on 18) The receiver according to claim 18, the receiver being configured to: downconvert the first subset of the downconverted plurality radio frequency signals from radio frequency bands in the first group; downconvert the second subset of the downconverted plurality radio frequency signals from radio frequency bands in the second group; receive a first subset of the downconverted plurality of radio frequency signals using the first bandpass filtered inphase and quadrature components; and receive a second subset of the downconverted plurality of radio frequency signals using the second bandpass filtered inphase and quadrature components. ### Claim 21 (depends on 20) The receiver according to claim 20, wherein the receiver further comprises: a plurality of analogue to digital converters configured to digitise the respective bandpass filtered inphase and quadrature components; and at least a digital image reject mixer to downconvert the digitised respective bandpass filtered inphase and quadrature components.