USER EQUIPMENT FOR PHYSICAL LAYER AUTOMATIC REPEAT REQUEST

• US 20100110991A1
• Filed: 01/07/2010
• Published: 05/06/2010
• Est. Priority Date: 08/24/2001
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Kwak, Joseph A.
• Granted Patent: US 8,102,801 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0034 where the transmitter decides based on inferences, e.g. use of implicit signalling
• CPC Class Codes: H04L 1/1809 Selective-repeat protocols
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1822 involving configuration of automatic repeat request [ARQ] with parallel processes
• CPC Class Codes: H04L 1/1845 Combining techniques, e.g. code combining
• CPC Class Codes: H04L 2001/0096 Channel splitting in point-to-point links
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A user equipment for physical layer automatic repeat request is disclosed. The user equipment comprises a higher layer automatic repeat request (ARQ) mechanism, a physical layer transmitter, a physical layer receiver, an acknowledgment (ACK) transmitter and an adaptive modulation and control unit (AMC). A higher layer ARQ mechanism generates data for transmission. A physical layer transmitter receives the data for transmission from the higher layer ARQ mechanism, to format the received data into packets for transmission. A physical layer receiver receives and demodulates received packets and retransmission statistics. An ACK transmitter transmits a corresponding acknowledgment for a given packet at the physical layer receiver. An AMC unit adjusts a particular encoding/data modulation of each packet using collected retransmission statistics.

Claims

1. A user equipment, comprising:

a higher layer automatic repeat request (ARQ) mechanism configured to generate data for transmission;

a physical layer transmitter configured to receive the data for transmission from the higher layer ARQ mechanism, to format the received data into packets for transmission, wherein the packets are transmitted using an orthogonal frequency division multiple access (OFDMA) air interface, the physical layer transmitter configured to retransmit an original or selectively modified packet, if an acknowledgment for that packet has not been received within a predetermined period of time;

a physical layer receiver configured to receive and demodulate received packets and retransmission statistics;

an ACK transmitter configured to transmit a corresponding acknowledgment for a given packet at the physical layer receiver, wherein a mechanism configured to receive the corresponding acknowledgment for the given packet operates transparently with respect to the higher layer ARQ mechanism; and

an adaptive modulation and control (AMC) unit configured to adjust a particular encoding/data modulation of each packet using collected retransmission statistics; and

wherein subchannels from an OFDM frequency set are selectively nulled wherein the use of a poor quality subchannel is precluded for a predetermined period and adding a previously nulled subchannel back into the OFDM frequency set where a retransmission rate or link quality indicates a high quality for the previously nulled subchannel.

2. The UE of claim 1, wherein the packets are transmitted using a single carrier having a frequency domain equalization (SC-FDE) air interface.

3. The UE of claim 1, wherein the received data is received in data blocks from the higher layer ARQ mechanism.

4. The UE of claim 1, wherein the particular encoding/data modulation is forward error correction (FEC).

5. The UE of claim 1, wherein a physical layer ARQ mechanism and the physical layer transmitter operate transparently with respect to the higher layer ARQ mechanism.

6. The UE of claim 1, wherein on condition that the collected retransmission statistics indicate a low number of retransmissions, a higher capacity encoding/data modulation scheme is selected as the particular encoding/data modulation and on condition that the collected retransmission statistics indicate a high number of retransmissions, a lower capacity encoding/data modulation scheme is selected as the particular encoding/data modulation.