DATA THROUGHPUT FOR CELL-EDGE USERS IN A LTE NETWORK USING DOWN-LINK REPEATERS AND UP-LINK HARQ RELAYS

• US 20120159279A1
• Filed: 12/13/2011
• Published: 06/21/2012
• Est. Priority Date: 12/16/2010
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Intel Corporation
• Inventors: BRAITHWAITE, RICHARD NEIL
• Granted Patent: US 8,918,692 B2
• Time in Patent Office: Days
• US Class Current: 714/751
• CPC Class Codes: H04B 7/155 Ground-based stations H04B7/204 takes precedence
• CPC Class Codes: H04B 7/15507 Relay station based processing for cell extension or control of coverage area, network planning with network coordinated processing with regard to cell extension H04W16/26; network topologies using dedicated repeater stations H04W84/047; terminal devices adapted for relaying to or from an other terminal H04W88/04
• CPC Class Codes: H04B 7/2606 Arrangements for base station coverage control, e.g. by using relays in tunnels
• CPC Class Codes: H04L 1/1816 with retransmission of the same, encoded, message
• CPC Class Codes: H04L 1/1822 involving configuration of automatic repeat request [ARQ] with parallel processes
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1893 Physical mapping arrangements physical resource mapping in general H04L5/00
• CPC Class Codes: H04L 2001/0097 Relays
• CPC Class Codes: H04W 40/22 using selective relaying for reaching a BTS [Base Transceiver Station] or an access point
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 84/047 using dedicated repeater stations

Abstract

A combination of repeaters and relays is used to improve the data throughput for user equipment (“UE”) near the cell edge in a LTE network. Amplify-and-forward repeaters and decode-and-forward relays enhance the down-link and up-link, respectively. Relay assistance on the up-link occurs when the evolved Node B (“eNB”) requests a retransmission (HARQ) from the UE at which point the UE and relay transmit simultaneously in a cooperative fashion. The quality of the up-link signal received by the eNB is improved due to a favorable channel through the relay. An analysis shows that relay assistance improves the throughput for a cell-edge user when the average delay per data transport block is allowed to increase.

Claims

1. A wireless communication system, comprising:

a base station configured for communication within a cell;

an up-link relay;

a down-link repeater co-located with the up-link relay;

a donor antenna coupled to the output of the up-link relay and further coupled to the input of the down-link repeater; and

,

a service antenna coupled to the input of the up-link relay and further coupled to the output of the down-link repeater.

2. The wireless communication system of claim 1, further comprising user equipment located within the cell, wherein the user equipment is configured for transmitting and receiving signals.

3. The wireless communication system of claim 2, wherein:

the up-link relay receives up-link signals, decodes the received up-link signals, recodes the decoded up-link signals, and transmits the recoded up-link signals; and

the down-link repeater receives down-link signals, amplifies the received down-link signals, and re-transmits the amplified down-link signals.

4. The wireless communication system of claim 3, wherein the wireless communication system employs automatic repeat requests in response to errors detected in received signals, wherein the base station further comprises a scheduler configured for controlling resource allocation for the up-link and the down-link signals.

5. The wireless communication system of claim 4, wherein:

the user equipment is configured for transmitting control signals to the base station via an up-link control channel during a repeat request retransmission period; and

,

the up-link relay is configured for transmitting data signals to the base station via an up-link shared channel during the repeat request retransmission period.

6. The wireless communication system of claim 5, wherein the up-link relay is configured for determining whether to re-transmit the up-link signals based on the operating protocol of the user equipment.

7. The wireless communication system of claim 4, wherein:

the user equipment is configured for transmitting control signals to the base station via an up-link control channel during a repeat request transmission period;

the user equipment is further configured for transmitting data signals to the base station via an up-link shared channel overlapping with the transmission of the control signals during the repeat request retransmission period; and

,

the up-link relay is configured for transmitting the data signals to the base station via the up-link shared channel during the repeat request retransmission.

11. The wireless communication system of claim 4, wherein the user equipment is further configured for transmitting control information directly to the base station when the up-link relay is transmitting.

8. The wireless communication system of 4, wherein the base station is further configured for scheduling and resource allocation for the up-link signals within the wireless communication system.

9. The wireless communication system of 4, wherein the up-link relay emulates a second user equipment to extract timing advance information.

10. The wireless communication system of 4, wherein the up-link relay emulates a second user equipment periodically to maintain power control and receive timing advance updates.

12. A method for wireless communication in a network, the network having a base station, user equipment, and a co-located up-link relay and down-link repeater, comprising:

transmitting down-link signals from a base station;

receiving the down-link signals transmitted from a base station by a down-link repeater via a donor antenna;

transmitting the down-link signals from the repeater via a service antenna;

receiving the down-link signals by the user equipment;

transmitting up-link signals by the user equipment;

receiving up-link signals transmitted from the user equipment by an up-link relay via the service antenna;

transmitting the up-link signals from the up-link relay via the donor antenna; and

,

receiving the up-link signals by the base station.

13. The method for wireless communication in a network, the network having a base station, user equipment, and a co-located up-link relay and down-link repeater as set out in claim 12, further comprising:

transmitting a repeat request from the base station to the user equipment and the up-link relay;

transmitting up-link control signals from the user equipment to the base station during a retransmission period;

transmitting up-link data signals from the up-link relay during the retransmission period; and

,

receiving the up-link control and data signals by the base station.

14. The method for wireless communication in a network, the network having a base station, user equipment, and a co-located up-link relay and down-link repeater as set out in claim 13, further comprising performing an incremental redundancy function of the up-link data signals.

15. The method for wireless communication in a network, the network having a base station, user equipment, and a co-located up-link relay and down-link repeater as set out in claim 13, further comprising:

determining whether to transmit up-link signals from the up-link relay based on the operating protocol of the user equipment.

16. The method for wireless communication in a network, the network having a base station, user equipment, and a co-located up-link relay and down-link repeater as set out in claim 12, further comprising:

transmitting a repeat request from the base station to the user equipment and the up-link relay;

transmitting up-link control and data signals from the user equipment to the base station during a retransmission period;

transmitting up-link data signals from the up-link relay to the base station during the retransmission period;

receiving the up-link control and data signals from the user equipment by the base station;

receiving the up-link data signals from the up-link relay by the base station; and

,

performing an incremental redundancy function of the up-link data signals from the user equipment and the up-link data signals from the up-link relay.

17. A method for wireless communication in a network, the network having a base station, user equipment, and a co-located up-link relay and down-link repeater, comprising:

transmitting down-link signals from a base station;

receiving the down-link signals by a down-link repeater via a donor antenna;

amplifying the down-link signals by a down-link repeater;

transmitting the amplified down-linked signals to a user equipment via a service antenna;

receiving the amplified down-link signals by the user equipment;

transmitting up-link signals from the user equipment;

receiving the up-link signals transmitted by the user equipment by an up-link relay via the service antenna;

decoding the up-link signals;

re-encoding the decoded up-link signals;

transmitting the re-encoded up-link signals to a base station via the donor antenna; and

,

receiving the up-link signals by the base station.

18. The method for wireless communication in a network, the network having a base station, user equipment, and a co-located up-link relay and down-link repeater as set out in claim 17, further comprising:

transmitting an automatic repeat request from the base station to the user equipment and the up-link relay;

transmitting up-link control signals via an up-link control channel from the user equipment to the base station during a retransmission period;

transmitting up-link data signals via an up-link shared channel from the up-link relay during the retransmission period; and

,

receiving the up-link control and data signals by the base station.

19. The method for wireless communication in a network, the network having a base station, user equipment, and a co-located up-link relay and down-link repeater as set out in claim 18, further comprising:

determining whether to transmit the up-link control signals based on the operating protocol of the user equipment.

20. The method for wireless communication in a network, the network having a base station, user equipment, and a co-located up-link relay and down-link repeater as set out in claim 17, further comprising:

transmitting a repeat request from the base station to the user equipment and the up-link relay;

transmitting control signals to the base station from the user equipment via an up-link control channel during a repeat request transmission period;

transmitting data signals to the base station from the user equipment via an up-link shared channel overlapping with the transmission of the control signals during the repeat request retransmission period;

transmitting up-link data signal from the up-link relay via the up-link shared channel to the base station during the retransmission period;

receiving the up-link control and data signals from the user equipment by the base station;

receiving the up-link data signals from the up-link relay by the base station; and

,

performing an incremental redundancy function of the up-link data signals from the user equipment and the up-link data signals from the up-link relay.