# US 11,122,648 B1 · Systems and methods for providing processing diversity transponder signals with distributed electronics > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,122,648 B1 - Document ID: US11122648B1 - Status: Granted - Kind: B1 - Application number: 15/930,211 - Filed: 2020-05-12 - Granted: 2021-09-14 - Earliest claimed: 2019-05-13 - Assignees: Aviation Communication & Surveillance Systems LLC - Applicants: Aviation Communication & Surveillance Systems, LLC - Inventors: James Roy Troxel - Web page: https://patentgrep.com/patent/US11122648B1 ## CPC - H04W 88/085: {Access point devices with remote components} - H04B 1/0064: {with separate antennas for the more than one band (H04B1/0053 takes precedence)} - H04B 1/0075: {using different intermediate frequencied for the different bands} - H04B 1/3805: with built-in auxiliary receivers - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04B: TRANSMISSION ## Abstract A distributed antenna system of an aircraft includes first and second antennas and corresponding first and second remote transceiver units (RTUs). Each RTU receives a radio signal from the corresponding antenna and includes a field-programmable gate array (FPGA)/digital signal processor (DSP). The FPGA/DSP of a second RTU receives a second signal corresponding to the radio signal from the second antenna and receives a first signal from the first RTU corresponding to the radio signal from the first antenna. The FPGA/DSP of a second RTU determines which of the first and second antennae will transmit a reply to an interrogation included in the radio signals from the first and second antennae, based on a comparison of the first signal and the second signal. ## Claims ### Claim 1 A distributed antenna system comprising: a first remote transceiver unit (RTU) connected to a first antenna and comprising a first field programmable gate array (FPGA)/digital signal provider (DSP) configured to receive a first digital intermediate frequency (IF) signal, corresponding to a first RF signal, comprising an interrogation, from the first antenna; a second RTU connected to a second antenna and comprising: a second FPGA/DSP configured to receive a second digital IF signal, corresponding to a second RF signal, comprising the interrogation, from the second antenna and to receive the first digital IF signal; wherein the second FPGA/DSP comprises comparison logic configured to determine which of the first antenna and the second antenna will transmit a reply to the interrogation, based on a comparison of the first digital RF signal and the second digital RF signal. ### Claim 2 (depends on 1) The system of claim 1, wherein: the first RTU further comprises a first receiver, connected to the first antenna and configured to receive the first RF signal from the first antenna; and the second RTU further comprises a second receiver, connected to the second antenna and configured to receive the second RF signal from the second antenna. ### Claim 3 (depends on 2) The system of claim 2, wherein the first receiver is a first 1030 MHz receiver and the second receiver is a second 1030 MHz receiver. ### Claim 4 (depends on 2) The system of claim 2, wherein the second RTU further comprises a supplemental receiver configured to receive, from the first RTU, a signal corresponding to the first RF signal and configured to output, to the second FPGA/DSP the first digital IF signal. ### Claim 5 (depends on 2) The system of claim 2, wherein the first receiver is further configured to output the first digital IF signal to the second FPGA/DSP. ### Claim 6 (depends on 1) The system of claim 1, wherein the second FPGA/DSP is further configured to output, to the first FPGA/DSP a control signal configured to control the first FPGA/DSP to output a reply to the interrogation via the first antenna. ### Claim 7 (depends on 1) The system of claim 1, wherein one of the first antenna and the second antenna comprises a top antenna and another of the first antenna and the second antenna comprises a bottom antenna. ### Claim 8 A distributed antenna system comprising: a first remote transceiver unit (RTU) connected to a first antenna and comprising: a first field programmable gate array (FPGA)/digital signal provider (DSP) configured to receive a first digital intermediate frequency (IF) signal, corresponding to a first RF signal, comprising an interrogation, from the first antenna; a second RTU connected to a second antenna and comprising: a second FPGA/DSP configured to receive a second digital IF signal, corresponding to a second RF signal, comprising the interrogation, from the second antenna; and a remote FPGA/DSP configured to receive a first signal corresponding to the first RF signal and to receive a second signal corresponding to the second RF signal; wherein the remote FPGA/DSP comprises comparison logic configured to determine which of the first antenna and the second antenna will transmit a reply to the interrogation. ### Claim 9 (depends on 8) The system of claim 8, wherein: the first RTU further comprises a first receiver, connected to the first antenna and configured to receive the first RF signal from the first antenna; and the second RTU further comprises a second receiver, connected to the second antenna and configured to receive the second RF signal from the second antenna. ### Claim 10 (depends on 9) The system of claim 9, wherein the first receiver is a first 1030 MHz receiver and the second receiver is a second 1030 MHz receiver. ### Claim 11 (depends on 8) The system of claim 8, wherein one of the first antenna and the second antenna comprises a top antenna and another of the first antenna and the second antenna comprises a bottom antenna. ### Claim 12 (depends on 8) The system of claim 8, wherein the remote FPGA/DSP is further configured to output, one of the first RTU and the second RTU, a control signal configured to control the transmission of a reply to the interrogation. ### Claim 13 A method of response to an interrogation received by a distributed antenna system, the method comprising: receiving, from a first antenna, a first radio frequency (RF) signal, comprising an interrogation, at a first remote transceiver unit (RTU); receiving, from a second antenna, a second RF signal, comprising the interrogation, at a second RTU disposed apart from the first RTU; at a FPGA/DSP, receiving a first digital intermediate frequency (IF) signal, corresponding to the first RF signal and receiving a second digital IF signal, corresponding to the second RF signal; the FPGA/DSP determining which of the first antenna and the second antenna will transmit a reply to the interrogation, based on a comparison of the first digital RF signal and the second digital RF signal. ### Claim 14 (depends on 13) The method of claim 13, wherein the FPGA/DSP is disposed within one of the first RTU and the second RTU. ### Claim 15 (depends on 13) The method of claim 13, wherein the FPGA/DSP is spaced apart from both the first RTU and the second RTU.