# US 10,873,362 B2 · Reuse of transmission resources for device to device communication > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,873,362 B2 - Document ID: US10873362B2 - Status: Granted - Kind: B2 - Application number: 16/323,843 - Filed: 2017-08-11 - Published: 2019-05-30 - Granted: 2020-12-22 - Earliest claimed: 2016-08-16 - Assignees: IPCom GmbH & Co. KG - Applicants: IPCom GmbH & Co. KG - Inventors: Maik Bienas; Andreas Schmidt; Martin Hans - Web page: https://patentgrep.com/patent/US10873362B2 ## CPC - H04B 1/7107: Subtractive interference cancellation - H04B 17/345: Interference values ({signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]} H04B17/336) - H04L 1/0038: {Blind format detection (for detection of modulation format H04L27/0012)} - H04L 27/0012: {arrangements for identifying the type of modulation} - H04W 4/70: Services for machine-to-machine communication [M2M] or machine type communication [MTC] - H04W 52/242: {taking into account path loss} - H04W 52/243: {taking into account interferences} - H04W 52/367: {Power values between minimum and maximum limits, e.g. dynamic range} - H04W 52/383: {power control in peer-to-peer links} - H04W 72/02: Selection of wireless resources by user or terminal - H04W 72/0473: {the resource being transmission power} - H04W 76/14: Direct-mode setup - H04W 88/023: {with message or information receiving capability} - H04W 88/06: adapted for operation in multiple networks {or having at least two operational modes}, e.g. multi-mode terminals - H04J 11/004: {using regenerative subtractive interference cancellation} - H04W 16/14: Spectrum sharing arrangements {between different networks} - H04B: TRANSMISSION - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) ## Abstract The present invention provides a method of determining a transmission power for device to device, D2D, transmissions between a first user equipment device and a second user equipment device using transmission resources being used for transmissions to a cellular network entity by a third user equipment device, the method comprising determining a measure of a path loss between the cellular network entity and the first user equipment device, and using the measure of the path loss to determine a maximum transmission power such that the D2D transmissions are received at the cellular network entity with a signal level around or below a noise level. ## Claims ### Claim 1 A method of determining a transmission power for device to device, D2D, transmissions between a first user equipment device and a second user equipment device using transmission resources being used for transmissions to a cellular network entity by a third user equipment device, the method comprising: measuring, by the first user equipment device, a received power of downlink reference signals received from the cellular network entity, determining, from the received power, a measure of a path loss from the cellular network entity to the first user equipment device, and using the measure of the path loss to determine a maximum transmission power such that the D2D transmissions are received at the cellular network entity with a signal level around or below a noise level, wherein the determining of the maximum transmission power includes using a correction value for compensating for a difference between the measured path loss from the cellular network entity to the first user equipment device and a path loss from the first user equipment device to the cellular network entity. ### Claim 2 (depends on 1) The method according to claim 1, wherein the measure of the path loss is determined by comparing a power of a signal received at the first user equipment device with a transmission power of that signal as indicated by the cellular network entity. ### Claim 3 (depends on 2) The method according to claim 2, wherein the maximum transmission power is determined using an equation P_Tx_D2D_max=P_Ref−RSRP+P_correct−P_offset where: P_Tx_D2D_max is the maximum transmission power; P_Ref is a transmit power of downlink reference signals as indicated in system information transmitted by the cellular network entity; RSRP is a measured power of the downlink reference signals at the first user equipment device; P_correct is the correction value to compensate a path loss difference of uplink versus downlink; and P_offset is a power offset value. ### Claim 4 (depends on 1) The method according to claim 1, wherein the correction value is determined by comparing an uplink transmission frequency and a downlink transmission frequency. ### Claim 5 (depends on 1) The method according to claim 1, wherein the first user equipment device derives the correction value and the maximum transmission power autonomously without a need to involve any cellular network entity. ### Claim 6 (depends on 1) The method according to claim 1, wherein the correction value is determined by multiplying a logarithm of a carrier frequency for the D2D transmissions divided by a carrier frequency of transmissions from the cellular network entity to the first user equipment device multiplied by a constant. ### Claim 7 A method of determining a transmission power for device to device, D2D, transmissions between a first user equipment device and a second user equipment device using transmission resources being used for transmissions to a cellular network entity by a third user equipment device, the method comprising: measuring, by the first user equipment device, a received power of downlink reference signals received from the cellular network entity; determining from the measured received power a measure of a path loss from the cellular network entity to the first user equipment device; and using the measure of the path loss to determine a maximum transmission power such that the D2D transmissions are received at the cellular network entity with a signal level around or below a noise level.