# US 10,484,040 B2 · Apparatus and method for cancelling self-interference signal in communication system supporting full-duplex scheme > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,484,040 B2 - Document ID: US10484040B2 - Status: Granted - Kind: B2 - Application number: 15/149,607 - Filed: 2016-05-09 - Published: 2016-11-10 - Granted: 2019-11-19 - Earliest claimed: 2015-05-07 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Jong-Bu Lim; Byung-Hwan Lee; Ji-Yun Seol; Tae-Young Kim; Min Sagong - Web page: https://patentgrep.com/patent/US10484040B2 ## CPC - H04B 1/58: Hybrid arrangements, i.e. arrangements for transition from single-path two-direction transmission to single-direction transmission on each of two paths or vice versa - H04B 1/525: with means for reducing leakage of transmitter signal into the receiver - H04L 5/14: Two-way operation using the same type of signal, i.e. duplex - H04B: TRANSMISSION - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract The present disclosure relates to a pre-5th-generation (5G) or 5G communication system to be provided for supporting higher data rates beyond 4th-generation (4G) communication system such as a long term evolution (LTE). A method for cancelling a self-interference (SI) signal in a communication system supporting a full-duplex scheme is provided. The method includes estimating an SI channel, performing a pre-filtering operation on a transmission signal based on the estimated SI channel, generating copied-SI signals based on the estimated SI channel, and cancelling an SI signal based on the copied-SI signals, wherein the pre-filtering operation includes an operation for decreasing a number of SI signals. ## Claims ### Claim 1 A method for cancelling a self-interference (SI) signal in a communication system supporting a full-duplex scheme, the method comprising: estimating an SI channel; performing a pre-filtering operation on a transmission signal based on the estimated SI channel; generating copied-SI signals based on the estimated SI channel and the pre-filtered transmission signal; and cancelling an SI signal based on the copied-SI signals, wherein the pre-filtering operation includes an operation for decreasing a number of SI signals, and wherein the performing of the pre-filtering operation on the transmission signal based on the estimated SI channel comprises: acquiring a pre-filter which is time reverse for the estimated SI channel and is a complex conjugate, and filtering the transmission signal based on the acquired pre-filter. ### Claim 2 (depends on 1) The method of claim 1, further comprising: transmitting the pre-filtered transmission signal. ### Claim 3 (depends on 1) The method of claim 1, further comprising: transmitting the pre-filtered transmission signal; and transmitting information related to the pre-filtering operation. ### Claim 4 (depends on 3) The method of claim 3, wherein the information related to the pre-filtering operation includes channel information for equalization of a receiving apparatus which receives the transmission signal. ### Claim 5 An apparatus for cancelling a self-interference (SI) signal in a communication system supporting a full-duplex scheme, the apparatus comprising: a first processor configured to estimate an SI channel, and to perform a pre-filtering operation on a transmission signal based on the estimated SI channel; and second processors configured to generate copied-SI signals based on the estimated SI channel and the pre-filtered transmission signal, wherein the first processor is further configured to cancel an SI signal based on the copied-SI signals, wherein the pre-filtering operation includes an operation for decreasing a number of SI signals, and wherein the first processor is configured to acquire a pre-filter which is time reverse for the estimated SI channel and is a complex conjugate, and filter the transmission signal based on the acquired pre-filter. ### Claim 6 (depends on 5) The apparatus of claim 5, further comprising: a transmitter configured to transmit the pre-filtered transmission signal and transmit information related to the pre-filtering operation. ### Claim 7 (depends on 6) The apparatus of claim 6, wherein the information related to the pre-filtering operation includes channel information for equalization of a receiving apparatus which receives the transmission signal. ### Claim 8 (depends on 5) The apparatus of claim 5, wherein the first processor is further configured to: estimate power delay profile for a reception signal, and control an operation of the second processors based on the estimated power delay profile. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein each of the second processors comprises variable gain controllers, variable phase controllers, and variable delay controllers. ### Claim 10 (depends on 9) The apparatus of claim 9, wherein each of the variable gain controllers, the variable phase controllers, and the variable delay controllers is controlled based on the estimated power delay profile. ### Claim 11 (depends on 5) The apparatus of claim 5, wherein the first processor is further configured to control an attenuation value for a reception signal. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the first processor is further configured to combine the pre-filtered transmission signal and the reception signal of which the attenuation value is controlled. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein the first processor is further configured to estimate an SI channel based on a signal that the copied-SI signals and the reception signal of which the attenuation value is controlled are combined. ### Claim 14 (depends on 12) The apparatus of claim 12, further comprising: a low noise amplifier configured to low noise amplify a signal that the copied-SI signals and the reception signal of which the attenuation value is controlled are combined. ### Claim 15 (depends on 5) The apparatus of claim 5, further comprising: a low noise amplifier configured to low noise amplify a reception signal. ### Claim 16 (depends on 15) The apparatus of claim 15, wherein the first processor is further configured to control an attenuation value for the low noise amplified signal. ### Claim 17 (depends on 16) The apparatus of claim 16, wherein the first processor is further configured to combine the pre-filtered transmission signal and the reception signal of which the attenuation value is controlled. ### Claim 18 (depends on 17) The apparatus of claim 17, wherein the first processor is further configured to estimate an SI channel based on a signal that the copied-SI signals and the reception signal of which the attenuation value is controlled are combined.