Coverage improvement in wireless systems with fixed infrastructure based relays

• US 7,406,060 B2
• Filed: 10/04/2005
• Issued: 07/29/2008
• Est. Priority Date: 07/06/2005
• Status: Expired due to Fees

• Current Assignee: RPX Clearinghouse LLC (RPX Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Wu, Shiquan, Periyalwar, Shalini
• Primary Examiner(s): FERGUSON, KEITH
• Application Number:
  US11/242,029
• Publication Number:
  US 20070010196A1
• Time in Patent Office: 1,029 Days
• Field of Search: 370/328, 370/315, 370/325, 370/334, 370/329, 370/336, 370/345, 370/431, 370/313, 370/339, 370/913, 370/75, 455/11.1, 455/422.1, 455/403, 455/500, 455/517, 455/445, 455/421, 455/550.1, 455/560, 455/561, 455/562.2, 455/553.1, 455/426.1, 455/426.2
• US Class Current: 370/328
• CPC Class Codes: H04B 7/026 Co-operative diversity, e.g. using fixed or mobile stations as relays
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/15528 Control of operation parameters of a relay station to exploit the physical medium
• CPC Class Codes: H04B 7/15592 Adapting at the relay station communication parameters for supporting cooperative relaying, i.e. transmission of the same data via direct - and relayed path cooperative diversity H04B7/024
• CPC Class Codes: H04B 7/2606 Arrangements for base station coverage control, e.g. by using relays in tunnels
• CPC Class Codes: H04L 25/20 Repeater circuits; Relay circuits

Abstract

Infrastructure relays are used to relay signals to multi-antenna receivers where the received signals are then processed using MIMO processing. The transmissions can use spatial multiplexing and/or space time block coding.

Claims

1. A method comprising:

a first wireless node transmitting to a second wireless node;

a third wireless node transmitting to the second wireless node;

the second wireless node performing MIMO processing on signals received from the first wireless node and the third wireless node;

wherein the third wireless node is a relay re-transmitting content received from a fourth wireless node, the fourth wireless node operating in a first mode of operation;

the first wireless node is a mobile station; and

the second wireless node is a base station.

2. The method of claim 1 further comprising providing a second mode of operation for the fourth node comprising:

the fourth node transmitting directly to the second node and to the third node;

the third node receiving from the fourth node and re-transmitting to the second node, the third and fourth node'"'"'s transmissions comprising a cooperative diversity transmission;

the second node receiving a direct transmission from the fourth node and the third node'"'"'s retransmission on multiple antennas and performing diversity combining;

the method further comprising;

adaptively selecting one of another MIMO mode and cooperative diversity.

3. The method of claim 1 further comprising the second node adaptively selecting one of a plurality of MIMO modes by:

for each MIMO mode determining a respective metric;

selecting between the plurality of MIMO modes based on the metrics.

4. A method comprising:

a first wireless node transmitting to a second wireless node;

a third wireless node transmitting to the second wireless node;

the second wireless node performing MIMO processing on signals received from the first wireless node and the third wireless node;

the first and third wireless nodes receiving signals from fourth and fifth wireless nodes respectively;

the first node transmitting content received from the Fourth wireless node to the third wireless node, and the third wireless node transmitting content received from, the fifth wireless node to the first wireless node;

wherein first wireless node transmitting to the second wireless node comprises transmitting a signal based on the content received from the third wireless node and also based on the content received from the fourth wireless node;

wherein the third wireless node transmitting to the second wireless node comprises transmitting a signal based on the content received from the first wireless node and also based on the content received from the fifth wireless node.

5. The method of claim 4 wherein:

the first and third wireless nodes are relays;

the second wireless node is a base station;

the fourth and fifth wireless nodes are mobile stations.

6. The method of claim 4 wherein

the first and third nodes transmissions together comprise an STTD (space time transmit diversity) transmission.

7. The method of claim 6 wherein:

the first and third wireless nodes are relays;

the second wireless node is a base station;

the fourth and fifth wireless nodes are mobile stations.