# US 7,609,627 B2 · Method for packet data transmission > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,609,627 B2 - Document ID: US7609627B2 - Status: Granted - Kind: B2 - Application number: 10/488,065 - Filed: 2002-08-14 - Published: 2004-12-02 - Granted: 2009-10-27 - Earliest claimed: 2001-08-27 - Inventors: Carola Beckmöller; Ralf Kern; Jürgen Schüling - Web page: https://patentgrep.com/patent/US7609627B2 ## CPC - H04W 28/06: Optimizing {the usage of the radio link}, e.g. header compression, information sizing {, discarding information (system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365)} - H04L 1/0009: {by adapting the channel coding (H04L1/1812 takes precedence)} - H04L 1/0034: {where the transmitter decides based on inferences, e.g. use of implicit signalling} - H04L 47/43: Assembling or disassembling of packets, e.g. segmentation and reassembly [SAR] - 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 method for packet data transmission in a communication system is disclosed, where the packet data includes a first type of data packet and at least one alternative second type of data packet. According to the method, quality modifications of a transmission channel used as a connection between a data source and data sinks are detected and, according to the detected quality modification, a data packet type of a successive data packet to be transmitted via the transmission channel is selected. ## Claims ### Claim 1 A method for packet data transmission in a Bluetooth radio communication system, wherein the packet data comprises a first data packet type and at least one different second data packet type, comprising the steps of: recording changes in a quality of a transmission channel used for a connection between a first data source and a data sink; depending on the changes in the quality recorded, switching back and forth between the first data packet type and the at least one different second data packet type for subsequent data packets to be sent over the transmission channel, wherein a) the first data packet type is a DM5 packet, and b) the at least one different second data packet type is a DH5 packet, and wherein the step of switching back and forth between the first data packet type and the at least one different second data packet type comprises determining if the first data source is a master data source or a slave data source, and if the first data source is the master, then the switch to another data packet type is made immediately, and if the first data source is the slave, then the switch to another data packet type is made after requesting to a master of the slave the data packet type switch. ### Claim 2 (depends on 1) The method according to claim 1, wherein based at least the recorded changes, transmitting the second data packet type, wherein the second data packet type features a lower proportion of control data than the first data packet type. ### Claim 3 (depends on 2) The method according to claim 2, wherein the second data packet type features a lower number of error coding bits compared to the first data packet type. ### Claim 4 (depends on 2) The method according to claim 2, wherein the good quality is signaled upon reaching a first threshold value of a variable reflecting the quality of the transmission channel. ### Claim 5 (depends on 2) The method according to claim 2, wherein, for a transmission channel with a bad quality, the first data packet type is selected, the bad quality being signaled when a second threshold value is reached. ### Claim 6 (depends on 1) The method according to claim 1, wherein the change in quality is recorded on the data source side. ### Claim 7 (depends on 1) The method according to claim 1, wherein a) the change in quality is recorded on the data sink side, and b) a message specifying the change in quality is transmitted from a data sink to the data source. ### Claim 8 (depends on 1) The method according to claim 1, wherein, to determine the change in quality, one of (a) a number of packet retries are recorded, and (b) a field strength measurement of received signals is taken, reflecting the quality of the transmission channel. ### Claim 9 A method for packet data transmission in a Bluetooth radio communication system, wherein the packet data comprises a DM5 data packet type and at least one DH5 data packet type, the method comprising the steps of: recording changes in a quality of a transmission channel used for a connection between a first data source and a data sink, wherein the changes in quality are defined by a first threshold and a second threshold; selecting a subsequent data packet type to be a DM5 data packet type if the change in the quality reaches the first threshold; selecting a subsequent data packet type to be a DH5 data packet type if the change in the quality reaches the second threshold; and switching back and forth between the DM5 data packet type and the at least one DH5 data packet type based on the changes in the quality of the transmission channel, wherein the step of switching back and forth between the DM5 packet type and the at least one DH5 data packet type comprises determining if the first data source is a master data source or a slave data source, and if the first data source is the master, then the switch to another data packet type is made immediately, and if the first data source is the slave, then the switch to another data packet type is made after requesting to a master of the slave the data packet type switch. ### Claim 10 (depends on 9) The method according to claim 9, wherein the first threshold indicates a better quality, compared to the second threshold.