# US 7,613,978 B2 · Method and an apparatus for a quick retransmission of signals in a communication system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,613,978 B2 - Document ID: US7613978B2 - Status: Granted - Kind: B2 - Application number: 11/518,329 - Filed: 2006-09-07 - Published: 2007-07-19 - Granted: 2009-11-03 - Earliest claimed: 2000-04-14 - Assignees: QUALCOMM Incorporated - Inventors: Ahmad Jalali; Eduardo A.S. Esteves; Nagabhushana T. Sindhushayana; Peter J. Black; Rashid A. Attar - Web page: https://patentgrep.com/patent/US7613978B2 ## CPC - H04L 1/1887: {Scheduling and prioritising arrangements} - H04L 1/1692: {Physical properties of the supervisory signal, e.g. acknowledgement by energy bursts} - H04L 1/1809: Selective-repeat protocols - H04L 1/1848: {Time-out mechanisms} - H04L 1/1877: {for semi-reliable protocols, e.g. for less sensitive applications like streaming video (buffer level management for video bitstream control arrangements H04N21/44004)} - H04L 1/188: {Time-out mechanisms} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A method and an apparatus for quick retransmission of signals in a communication system are disclosed. A transmitting terminal, e.g., a base station, transmits signals in a form of packets to a receiving terminal, e.g., a subscriber station. The receiving terminal determines if the packet was intended for the receiving terminal, and if so, the receiving terminal demodulates the packet. The receiving terminal then computes a quality metric of the packet, and compares the computed quality metric with a quality metric contained in the packet. If the quality metrics match, the packet is declared correctly received, and is forwarded for further processing. If the quality metrics fail to match, the receiving terminal sends a request for retransmission of the packet. The transmitting terminal determines which packet needs to be retransmitted based on the request for retransmission. The transmitting terminal then schedules the packet for retransmission. ## Claims ### Claim 1 A method for wireless communication, comprising: receiving data in multiple forward link timeslots; determining a quality metric of the received data; requesting retransmission of the received data if the quality metric indicates the received data has not been received correctly; and if retransmission is requested and not received, performing a secondary scheme capable of again requesting retransmission of the received data. ### Claim 2 (depends on 1) The method of claim 1, wherein a preamble is received in each of the multiple forward link timeslots. ### Claim 3 (depends on 1) The method of claim 1, wherein a preamble is received in only a first of the multiple forward link timeslots. ### Claim 4 (depends on 2) The method of claim 2, wherein the step of requesting retransmission comprises: comparing the determined quality metric of the received data with a quality metric contained in at least one slot of the multiple timeslots; and generating a retransmission request based on said comparison. ### Claim 5 (depends on 4) The method of claim 4 further comprising: transmitting the retransmission request at a determinable time instant. ### Claim 6 An apparatus for wireless communication, comprising: a receiver operative to receive data in multiple forward link timeslots; a processor operative to determine a quality metric of the received data; and a transmitter operative to request retransmission of the received data if the quality metric indicates the received data has not been received correctly; and if retransmission is requested and not received, to perform a secondary scheme capable of again requesting retransmission of the received data. ### Claim 7 (depends on 6) The apparatus of claim 6, wherein: the receiver is further operative to receive a preamble in each of the multiple forward link timeslots. ### Claim 8 (depends on 6) The apparatus of claim 6, wherein: the receiver is further operative to receive a preamble in only a first of the multiple forward link timeslots. ### Claim 9 (depends on 7) The apparatus of claim 7, wherein: the transmitter is further operative to (a) compare the determined quality metric of the received data with a quality metric contained in at least one slot of the multiple timeslots; and (h) generate a request based on said comparison. ### Claim 10 (depends on 9) The apparatus of claim 9 wherein: the transmitter is further operative to transmit the retransmission request at a determinable time instant. ### Claim 11 An apparatus for wireless communication, comprising: receiver means operative to receive data in multiple forward link timeslots; processor means operative to determine a quality metric of the received data; and transmitter means operative to request retransmission of the received data if the quality metric indicates the received data has not been received correctly; and if retransmission is requested and not received, to perform a secondary scheme capable of again requesting retransmission of the received data. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein: the receiver means is further operative to receive a preamble in each of the multiple forward link timeslots. ### Claim 13 (depends on 11) The apparatus of claim 11, wherein: the receiver means is further operative to receive a preamble in only a first of the multiple forward link timeslots. ### Claim 14 (depends on 12) The apparatus of claim 12, wherein: the transmitter means is further operative to (a) compare the determined quality metric of the received data with a quality metric contained in at least one slot of the multiple timeslots; and (b) generate a request based on said comparison. ### Claim 15 (depends on 14) The apparatus of claim 14 wherein: the transmitter means is further operative to transmit the retransmission request at a determinable time instant.