MIMO WIRELESS COMMUNICATION SYSTEM, MIMO TRANSMISSION METHOD, AND APPARATUS

• US 20150049736A1
• Filed: 10/30/2014
• Published: 02/19/2015
• Est. Priority Date: 05/02/2012
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: LIU, Sheng, YU, Rongdao, WANG, Rui
• Granted Patent: US 9,693,378 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04B 7/026 Co-operative diversity, e.g. using fixed or mobile stations as relays
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04W 52/143 Downlink power control
• CPC Class Codes: H04W 52/242 taking into account path loss
• CPC Class Codes: H04W 52/383 power control in peer-to-peer links
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 76/14 Direct-mode setup

Abstract

Embodiments of the present invention provide a MIMO wireless communication system, a MIMO transmission method, and an apparatus, which relate to the field of communications technologies and are invented to effectively improve transmission efficiency and decrease a transmission delay. The MIMO wireless communication system includes: a base station, a first user equipment, and at least one second user equipment, where the first user equipment performs cellular uplink communication with the base station, and performs device-to-device communication with the at least one second user equipment, and the same time-frequency resource is used in the cellular uplink communication between the first user equipment and the base station and the device-to-device communication between the first user equipment and the second user equipment. The present invention is applicable to wireless communication technologies.

Claims

1. A multiple-input multiple-output transmission method, comprising:

performing, by a first user equipment, cellular uplink communication with a base station; and

performing, by the first user equipment, device-to-device communication with at least one second user equipment, wherein

a same time-frequency resource is used in the cellular uplink communication and the device-to-device communication.

2. The transmission method according to claim 1, further comprising:

using, by the first user equipment, a first precoding matrix to perform precoding processing on data transmitted in the cellular uplink communication, so as to make interference of the cellular uplink communication in the device-to-device communication lower than a first specified threshold; and

using, by the first user equipment, a second precoding matrix to perform precoding processing on data transmitted in the device-to-device communication, so as to make interference of the device-to-device communication in the cellular uplink communication lower than a second specified threshold.

3. The transmission method according to claim 1, further comprising:

determining, by the first user equipment, transmit power of the device-to-device communication according to path loss of a device-to-device communication link; and

determining, by the first user equipment, transmit power of the cellular uplink communication according to the determined transmit power of the device-to-device communication and path loss of a cellular uplink communication link, wherein

the performing, by the first user equipment, the cellular uplink communication with the base station comprises;

using, by the first user equipment, the determined transmit power of the cellular uplink communication to perform the cellular uplink communication with the base station; and

the performing, by the first user equipment, the device-to-device communication with the at least one second user equipment comprises;

using, by the first user equipment, the determined transmit power of the device-to-device communication to perform the device-to-device communication with the second user equipment.

4. The transmission method according to claim 1, further comprising:

performing, by the first user equipment, precoding processing on data transmitted in the cellular uplink communication and data transmitted in the device-to-device communication in a superposition coding manner, wherein

transmit power used in the cellular uplink communication performed by the first user equipment is higher than transmit power used in the device-to-device communication performed by the user equipment, so as to enable the base station to process a signal of the device-to-device communication as noise, when receiving an uplink signal of the cellular uplink communication, and to enable the second user equipment to first perform interference elimination on the uplink signal of the cellular uplink communication, when receiving the signal of the device-to-device communication.

5. A user equipment, comprising:

a first communication unit, configured to perform cellular uplink communication with a base station; and

a second communication unit, configured to perform device-to-device communication with at least one second user equipment, wherein

a same time-frequency resource is used in the cellular uplink communication and the device-to-device communication.

6. The user equipment according to claim 5, further comprising:

a first precoding unit, configured to use a first precoding matrix to perform precoding processing on data transmitted in the cellular uplink communication, so as to make interference of the cellular uplink communication in the device-to-device communication lower than a first specified threshold; and

a second precoding unit, configured to use a second precoding matrix to perform precoding processing on data transmitted in the device-to-device communication, so as to make interference of the device-to-device communication in the cellular uplink communication lower than a second specified threshold.

7. The user equipment according to claim 6, further comprising:

a determining unit, configured to determine transmit power of the device-to-device communication according to path loss of a device-to-device communication link, and determine transmit power of the cellular uplink communication according to the determined transmit power of the device-to-device communication and path loss of the cellular uplink communication link, wherein

the first communication unit is further configured to use the transmit power, which is determined by the determining unit and is of the cellular uplink communication, to perform the cellular uplink communication with the base station; and

the second communication unit is further configured to use the transmit power, which is determined by the determining unit and is of the device-to-device communication, to perform the device-to-device communication with the second user equipment.

8. The user equipment according to claim 5, further comprising:

a superposition precoding unit, configured to perform precoding processing on data transmitted in the cellular uplink communication and data transmitted in the device-to-device communication in a superposition coding manner, wherein

transmit power of the cellular uplink communication performed by the first communication unit is higher than transmit power of the device-to-device communication performed by the second communication unit.

9. A multiple-input multiple-output wireless communication system, comprising:

a base station, a first user equipment, and at least one second user equipment, wherein

the first user equipment performs cellular uplink communication with the base station, and performs device-to-device communication with the at least one second user equipment, and

a same time-frequency resource is used in the cellular uplink communication between the first user equipment and the base station and the device-to-device communication between the first user equipment and the second user equipment.

10. The wireless communication system according to claim 9, wherein

the first user equipment uses a first precoding matrix to perform precoding processing on data transmitted in the cellular uplink communication, so as to make interference of the cellular uplink communication in the device-to-device communication lower than a first specified threshold;

and

the first user equipment uses a second precoding matrix to perform precoding processing on data transmitted in the device-to-device communication, so as to make interference of the device-to-device communication in the cellular uplink communication lower than a second specified threshold.

11. The wireless communication system according to claim 10, wherein

the first user equipment determines transmit power of the device-to-device communication according to path loss of a device-to-device communication link, and uses the determined transmit power of the device-to-device communication to perform the device-to-device communication with the second user equipment;

and

the first user equipment determines transmit power of the cellular uplink communication according to the determined transmit power of the device-to-device communication and path loss of a cellular uplink communication link, and uses the determined transmit power of the cellular uplink communication to perform the cellular uplink communication with the base station.

12. The wireless communication system according to claim 10, wherein

the second user equipment performs cellular uplink communication with the base station;

the same time-frequency resource is used in the cellular uplink communication between the first user equipment and the base station, the device-to-device communication between the first user equipment and the second user equipment, and the cellular uplink communication between the second user equipment and the base station; and

when receiving a signal of the device-to-device communication, the second user equipment performs interference elimination on a signal of the cellular uplink communication between the second user equipment and the base station.

13. The wireless communication system according to claim 9, wherein

the first user equipment performs precoding processing on data transmitted in the cellular uplink communication and data transmitted in the device-to-device communication in a superposition coding manner;

transmit power of the cellular uplink communication performed by the first user equipment is higher than transmit power of the device-to-device communication performed by the first user equipment;

when receiving an uplink signal of the cellular uplink communication, the base station processes a signal of the device-to-device communication as noise; and

when receiving the signal of the device-to-device communication, the second user equipment first performs interference elimination on the uplink signal of the cellular uplink communication.

14. The wireless communication system according to claim 13, wherein

the second user equipment learns, from the base station or the first user equipment, a precoding matrix used in the cellular uplink communication;

and

when receiving the signal of the device-to-device communication, the second user equipment obtains the uplink signal of the cellular uplink communication according to the learned precoding matrix, and then performs interference elimination on the obtained uplink signal of the cellular uplink communication.

15. The wireless communication system according to claim 9, wherein

the wireless communication system further comprises a third user equipment, wherein the third user equipment performs cellular uplink communication with the base station;

the same time-frequency resource is used in the cellular uplink communication between the third user equipment and the base station, the cellular uplink communication between the first user equipment and the base station, and the cellular uplink communication between the second user equipment and the base station; and

a distance between the third user equipment and the first user equipment is greater than a specified distance.

16. The wireless communication system according to claim 9, wherein

the wireless communication system further comprises a third user equipment, wherein the third user equipment performs cellular uplink communication with the base station;

the same time-frequency resource is used in the cellular uplink communication between the third user equipment and the base station, the cellular uplink communication between the first user equipment and the base station, and the cellular uplink communication between the second user equipment and the base station; and

the third user equipment performs, by using a specific precoding matrix, precoding processing on data transmitted in the cellular uplink communication between the third user equipment and the base station, so as to make interference of the cellular uplink communication between the third user equipment and the base station in the device-to-device communication be zero or lower than a specified threshold.