Patent•
Multi-user beam-forming method and device
11 Aug 2010-
TL;DR: In this article, a multi-user beamforming method and device which is applicable to the MIMO wireless communication system based on TDD is presented, where the downlink channel information of each user is obtained according to uplink channel information, and the DOA estimation algorithm is adopted to obtain the do-a-day (DOA) information of the user according to the down-link channel.
Abstract: The invention discloses a multi-user beam-forming method and device which are applicable to the MIMO wireless communication system based on TDD. In the scheme of the invention, the downlink channel information of each user is obtained according to uplink channel information, the DOA estimation algorithm is adopted to obtain the DOA information of each user according to the downlink channel information; and the users are paired, the users satisfying set constraint conditions constitute a paired user group, the null widening algorithm is adopted to calculate the weight of beam of each user according to the DOA information of each user in the paired user group; and the beam corresponding to the weight of beam of each user has the following properties: main lobe is generated in the corresponding DOA direction of each user, and broad-range nulls are generated in the DOA directions of other users in the paired user group. Only multi-antenna technology and beam null widening technology are used under the condition of not using codes so that at least two users can use the same time, frequency and code resources and the effective reuse of system resources can be realized.
Citations
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Patent•
25 Sep 2015TL;DR: In this article, a UE transmits a sounding reference signal to the base station, which characterizes the uplink channel based on the SRS received and, using reciprocity, applies the channel characterization for the downlink channel.
Abstract: Systems and techniques are disclosed to enhance the efficiency of available bandwidth between UEs and base stations. A UE transmits a sounding reference signal to the base station, which characterizes the uplink channel based on the SRS received and, using reciprocity, applies the channel characterization for the downlink channel. The base station may form the beam to the UE based on the uplink channel information obtained from the SRS. As the downlink channel changes the base station needs updated information to maintain its beamforming, meaning it needs a new SRS. Transmission of the SRS takes resources; to minimize this, the UE or the base station can determine a period during which the downlink channel will predictably remain coherent and set up a schedule for sending SRS. Alternatively, the UE or the base station can determine on demand that the channel is losing coherence and initiate an on demand SRS.
17 citations
Patent•
21 Jan 2015TL;DR: In this article, techniques, methods, and apparatuses for generating pilot sequences for use in uplink (UL) multi-user multiple input-multiple output (MU-MIMO) transmissions are described.
Abstract: Certain aspects of the present disclosure relate to techniques, methods, and apparatuses for generating pilot sequences for use in uplink (UL) multi-user multiple input-multiple output (MU-MIMO) transmissions.
14 citations
Patent•
28 Jun 2012
TL;DR: In this article, a feedback method and a feedback device of an MIMO wireless communication system for a downlink is presented, where a grouping principle is provided, based on implicit feedback, for grouping directions of beams sent by a base station.
Abstract: Disclosed are a feedback method and a feedback device of an MIMO wireless communication system for a downlink. In the feedback method, a grouping principle is provided, based on implicit feedback, for grouping directions of beams sent by a base station, a user end and a base station end know the grouping principle, and the user end and the base station end perform relevant work flows according to the grouping principle. Through the feedback method and device provided in the present invention, pairing of MU-MIMO may be completed only by only slightly increasing feedback overheads for the MU-MIMO, and the quantity of fed back bits is small, so interference between paired users can be reduced, and the frequency utilization rate of the entire system can be increased. The method and the device of the present invention are applicable to downlink MU-MIMO transmission of a cellular mobile communication system.
12 citations
Patent•
27 Mar 2014
TL;DR: In this paper, the authors describe the resource allocation and D2D discovery hopping in a user equipment (UE) and a method for resource allocation in the context of LTE-U. In some embodiments, the UE may receive signaling from an enhanced node B (eNB) indicating discovery resources to transmit discovery signals on within an LTE operation zone.
Abstract: Embodiments of a user equipment (UE) and method for resource allocation and device-to-device (D2D) discovery hopping are generally described herein. In some embodiments, the UE may receive signaling from an enhanced node B (eNB) indicating discovery resources to transmit discovery signals on within an LTE operation zone. The discovery resources may include a discovery zone which may comprise a plurality of physical resource blocks (PRBs) and a plurality of subframes. The UE may transmit a discovery signal for receipt by one or more other UEs for D2D discovery within some of the PRBs of the discovery zone. The PRBs for the transmission of the discovery signal may be determined in accordance with a hopping mode to provide increased frequency diversity within a bandwidth of the discovery zone. The hopping mode may comprise intra-subframe hopping, inter-subframe hopping or joint intra/inter-subframe hopping.
11 citations
Patent•
10 Aug 2011
TL;DR: In this paper, a method and system for scheduling channel resources and a base station, which are applied to the technical field of communication, is presented, which comprises the steps of pre-scheduling user equipment corresponding to a downlink resource in at least one subframe by the base station first before scheduling an uplink resource so as to obtain prescheduled user equipment information.
Abstract: The embodiment of the invention discloses a method and system for scheduling channel resources and a base station, which are applied to the technical field of communication. In the embodiment, the method comprises the steps of pre-scheduling user equipment corresponding to a downlink resource in at least one subframe by a base station first before scheduling an uplink resource so as to obtain pre-scheduled user equipment information, wherein the pre-scheduled user equipment information is referred to during scheduling the uplink resource; sending the scheduled uplink resource information to the scheduled user equipment by uplink authorization; calculating a downlink transmission weight of a NF (Null Forming) after receiving uplink channel information of the user equipment; scheduling a downlink frequency band of the user equipment to be a frequency band as same as the uplink channel information sent by the user equipment while at least one pre-scheduled subframe comes; and sending thedownlink resource information to the user equipment according to the calculated NF downlink transmission weight. According to the method in the embodiment, the interference between cells can be reduced and an effect of the NF on interference inhibition is improved.
7 citations