# US 12,120,620 B2 · Multiplex time division duplex (TDD) sync detection module > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,120,620 B2 - Document ID: US12120620B2 - Status: Granted - Kind: B2 - Application number: 16/885,218 - Filed: 2020-05-27 - Published: 2020-12-03 - Granted: 2024-10-15 - Earliest claimed: 2019-05-29 - Assignees: Wilson Electronics, LLC - Applicants: Wilson Electronics, LLC - Inventors: Christopher Ken Ashworth; Dale Robert Anderson - Web page: https://patentgrep.com/patent/US12120620B2 ## CPC - H04B 7/15542: {Selecting at relay station its transmit and receive resources (selection of wireless resources by user or terminal H04W72/02; arrangements affording multiple use of the transmission path by two-dimensional division of the resources H04L5/0003, or by allocating sub-channels H04L5/003)} - H04W 56/0005: {synchronizing of arrival of multiple uplinks} - H04B 7/15507: {Relay station based processing for cell extension or control of coverage area, (network planning with network coordinated processing with regard to cell extension H04W16/26; network topologies using dedicated repeater stations H04W84/047; terminal devices adapted for relaying to or from an other terminal H04W88/04)} - H04L 5/14: Two-way operation using the same type of signal, i.e. duplex - H04L 5/003: {Arrangements for allocating sub-channels of the transmission path} - H04B: TRANSMISSION - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A technology is described for a repeater that can comprise: a first port; a second port; a first amplification and filtering path coupled between the first port and the second port, wherein the first amplification and filtering path is configured to amplify and filter a first time division duplex (TDD) signal in a first frequency range of a first TDD uplink (UL) signal; a second amplification and filtering path coupled between the first port and the second port, wherein the second amplification and filtering path is configured to amplify and filter a second TDD signal in a second frequency range of a second TDD downlink (DL) signal; and a modem configured to generate an UL/DL indication signal for the first frequency range, and send the UL/DL indication signal to the repeater. ## Claims ### Claim 1 A repeater comprising: a first port; a second port; a first amplification and filtering path coupled between the first port and the second port, wherein the first amplification and filtering path is configured to amplify and filter a first time division duplex (TDD) uplink (UL) signal in a first frequency range; a second amplification and filtering path coupled between the first port and the second port, wherein the second amplification and filtering path is configured to amplify and filter a first TDD downlink (DL) signal in the first frequency range; a third amplification and filtering path coupled between the first port and the second port, wherein the third amplification and filtering path is configured to amplify and filter a second TDD UL signal in a second frequency range; and a fourth amplification and filtering path coupled between the first port and the second port, wherein the fourth amplification and filtering path is configured to amplify and filter a second TDD DL signal in the second frequency range; and a modem configured to: receive, for the TDD UL signal and the TDD DL signal, synchronization information for the first frequency range and UL/DL configuration information for the first frequency range; generate an UL/DL indication signal for the first frequency range from the synchronization information and the UL/DL configuration information for the first frequency range; and send the UL/DL indication signal to the repeater; receive the UL/DL indication signal at the repeater for the first frequency range; generate a switching signal for a first set of one or more switches to switch between the first amplification and filtering path and the second amplification and filtering path based on the UL/DL indication signal; and send the switching signal to the first set of one or more switches to enable amplification of the first TDD UL signal or the first TDD DL signal; generate a second UL/DL indication signal for the second frequency range; and send the second UL/DL indication signal to the repeater. ### Claim 2 (depends on 1) The repeater of claim 1, wherein the repeater is further configured to: receive the second UL/DL indication signal for the second frequency range; generate a second switching signal for a second set of one or more switches to switch between the third amplification and filtering path and the fourth amplification and filtering path based on the second UL/DL indication signal; and send the second switching signal to the second set of one or more switches to enable amplification of the second TDD UL signal or the second TDD DL signal. ### Claim 3 (depends on 1) The repeater of claim 1, wherein the repeater is further configured to: use the UL/DL indication signal to switch between: the first TDD UL signal; and the first TDD DL signal. ### Claim 4 (depends on 1) The repeater of claim 1, wherein the modem is further configured to: receive synchronization information for the first frequency range to enable the controller to switch between: the first TDD UL signal; and the first TDD DL signal. ### Claim 5 (depends on 4) The repeater of claim 4, wherein the modem is further configured to: receive synchronization information for the first frequency range from a base station transmitting the first TDD DL signal. ### Claim 6 (depends on 1) The repeater of claim 1, wherein the repeater is further configured to: use the UL/DL indication signal for the first frequency range to switch between the first TDD UL signal and the first TDD DL signal, wherein the UL/DL indication signal is generated from synchronization information for the first frequency range and UL/DL configuration information for the first frequency range. ### Claim 7 (depends on 1) The repeater of claim 1, wherein the modem is further configured to: store the UL/DL indication signal for the first frequency range. ### Claim 8 (depends on 7) The repeater of claim 7, wherein the modem is further configured to: use the UL/DL indication signal for the first frequency range that is stored at the modem to reacquire UL/DL indication information for the first frequency range in a subsequent time period. ### Claim 9 (depends on 1) The repeater of claim 1, wherein the UL/DL indication signal is generated from synchronization information for the first frequency range and UL/DL configuration information for the first frequency range. ### Claim 10 (depends on 1) The repeater of claim 1, wherein the first frequency range includes: one or more of: Third Generation Partnership Project (3GPP) long term evolution (LTE) time division duplex (TDD) frequency bands 33-53; or one or more of: 3GPP fifth generation (5G) TDD frequency bands n34, n38, n39, n40, n41, n50, n51, n77, n78, n79, n257, n258, n260, or n261. ### Claim 11 (depends on 1) The repeater of claim 1, wherein the modem is further configured to generate the UL/DL indication signal for the first frequency range without a subscriber identity module (SIM) card. ### Claim 12 (depends on 1) The repeater of claim 1, wherein the modem comprises a long term evolution (LTE) layer-1 modem configured to generate the UL/DL indication signal without using LTE layer-2 or LTE layer-3. ### Claim 13 (depends on 1) The repeater of claim 1, wherein the repeater is further configured to: switch from the first TDD DL signal to the first TDD UL signal directly within a first selected time period after downlink pilot time slot (DwPTS) symbols in a special subframe of the first TDD DL signal; and switch from the first TDD UL signal to the first TDD DL signal within a second selected time period after a subframe boundary between a UL subframe of the first TDD signal and a DL subframe of the first TDD DL signal. ### Claim 14 (depends on 13) The repeater of claim 13, wherein: the first selected time period is less than one or more of: 1 mcs, 500 nanoseconds, 300 nanoseconds, 200 nanoseconds, or 100 nanoseconds; and the second selected time period is less than one or more of: 1 mcs, 500 nanoseconds, 300 nanoseconds, 200 nanoseconds, or 100 nanoseconds. ### Claim 15 (depends on 13) The repeater of claim 13, wherein the repeater is further configured to: switch from the first TDD DL signal to the first TDD UL signal without using a timing advance (TA) value received from the UE; or switch from the first TDD UL signal to the first TDD DL signal without using the TA value received from the UE.