# US 7,613,987 B2 · Method for wireless data transmission > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,613,987 B2 - Document ID: US7613987B2 - Status: Granted - Kind: B2 - Application number: 11/080,441 - Filed: 2005-03-16 - Published: 2005-09-22 - Granted: 2009-11-03 - Earliest claimed: 2004-03-16 - Assignees: Atmel Automotive GmbH - Inventors: Ulrich Friedrich - Web page: https://patentgrep.com/patent/US7613987B2 ## CPC - G06K 7/10059: {transponder driven} - G06K 7/0008: {General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer} - G06K: GRAPHICAL DATA READING (image or video recognition or understanding G06V); PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS ## Abstract A method for wireless data transmission between a base station and one or more, in particular passive, transponders is provided, in which electromagnetic carrier waves are emitted by the base station. Data comprising successive characters are transmitted from a respective transponder to the base station by modulation and backscattering of the electromagnetic carrier waves, and a respective one of the characters is coded and transmitted by a respective transponder within a predefined time interval. Within at least one of the predefined time intervals, a safeguard character formed from the data to be transmitted is transmitted in addition to the character to be transmitted. ## Claims ### Claim 1 A method for wireless data transmission between a base station and one or more transponders, the method comprising the steps of: emitting electromagnetic carrier waves by the base station; transmitting data comprising successive characters from a respective transponder by modulation and backscattering of the electromagnetic carrier waves; and coding and transmitting a respective one of the characters by the respective transponder within a predefined time interval for coding and transmitting a single character; wherein, within at least one of the predefined time intervals, a safeguard character formed from the data to be transmitted is transmitted in addition to the character to be transmitted. ### Claim 2 (depends on 1) The method according to claim 1, wherein the modulation of the transmitted data is a PSK modulation or a ASK modulation. ### Claim 3 (depends on 1) The method according to claim 1, wherein the coding is a 3phase1 coding, an FM0 coding, or an NRZI coding. ### Claim 4 (depends on 1) The method according claim 1, wherein the predefined time interval is predefined by the base station by successive synchronization marks. ### Claim 5 (depends on 4) The method according to claim 4, wherein the successive synchronization marks are generated by field gaps or by a phase reversal of the electromagnetic carrier wave. ### Claim 6 (depends on 1) The method according to claim 1, wherein the safeguard character is part of a cyclic redundancy code formed from the data. ### Claim 7 (depends on 1) The method according to claim 1, wherein the safeguard character is a parity bit. ### Claim 8 (depends on 1) The method according to claim 1, wherein the safeguard character is coded by an additional modulation state that does not code a character. ### Claim 9 (depends on 8) The method according to claim 8, wherein the additional modulation state is generated by driving a varactor in an input circuit of the transponder. ### Claim 10 (depends on 1) The method according to claim 1, wherein the safeguard character is transmitted within the predefined time interval after the character that is to be transmitted. ### Claim 11 (depends on 1) The method according to claim 1, wherein the characters are part of an identification bit sequence which is transmitted from a transponder to the base station during a transponder selection method. ### Claim 12 (depends on 1) The method according to claim 1, wherein the transponder is a passive transponder. ### Claim 13 (depends on 1) The method according to claim 1, wherein the transponder transmits the data comprising successive characters to the base station or another base station. ### Claim 14 (depends on 1) The method according to claim 1, further comprising: forming the safeguard character from the data including the successive characters. ### Claim 15 (depends on 1) The method according to claim 1, wherein the safeguard character is transmitted during the transmission of the data. ### Claim 16 A method for wireless transmission between a base and at least one transponder, the method comprising the steps of: determining a coding type; forming a safeguard character from payload data; and selecting a predefined time interval corresponding to transmission of a single character for transmitting the safeguard data and the payload data based upon the determination of the coding type. ### Claim 17 (depends on 16) The method according to claim 16, further comprising: transmitting the safeguard data and the payload data within the predefined time interval. ### Claim 18 (depends on 16) The method according to claim 16, further comprising: transmitting the safeguard data during transmission of the payload data. ### Claim 19 A wireless transponder, comprising: an execution unit; a memory functionally coupled to the execution unit, containing instructions causing the processor to determine a coding type, form a safeguard character from payload data, and select a predefined time interval corresponding to transmission of a single character for transmitting the safeguard data and the payload data; and a multiplexer functionally coupled to the execution unit, which combines payload data and safeguard data based upon intervals determined by the execution unit. ### Claim 20 A method for wireless data transmission between a base station and one or more transponders, the method comprising: emitting electromagnetic carrier waves by the base station; transmitting data including successive characters from a respective transponder by modulation and backscattering of the electromagnetic carrier waves; coding and transmitting a respective one of the characters by the respective transponder within a predefined time interval for coding and transmitting a single character; forming a safeguard character from the data including the successive characters; and transmitting the safeguard character within a same predefined time interval as the transmitting of the respective one of the characters.