Aspects of the present invention provide additional MAC functionality to support the PHY features of a wireless communication system framework. The additional MAC functionality aids in enabling feedback from wireless terminals to base stations. In some aspects of the invention the feedback is provided on an allocated feedback channel. In other aspects of the invention the feedback is provided by MAC protocol data units (PDU) in a header, mini-header, or subheader. The feedback may be transmitted from the wireless terminal to the base station autonomously by the wireless terminal or in response to an indication from the base station that feedback is requested. Aspects of the invention also provide for allocating feedback resources to form a dedicated feedback channel. One or more of these enhancements is included in a given implementation. Base stations and wireless terminals are also described upon which methods described herein can be implemented.

A base station, e.g., for massive MIMO, has channel receivers, each connected to a respective antenna among a plurality of antennas to receive an RF transmission signal generated by a communication device (CD). Each channel receiver has a channel front-end module, which has a first bandwidth and converts the RF transmission signal into one or more first analog baseband signals. The channel receivers are collectively operable to define a spatial beam focus at the CD, based on channel state information of the CD. The base station has pilot signal receivers, each connected to a respective antenna among the plurality of antennas to receive an RF pilot signal generated by the CD or another CD. Each pilot signal receiver has a pilot signal front-end module, which has a second bandwidth that is smaller than the first bandwidth and converts the RF pilot signal into one or more second analog baseband signals.

Apparatuses, methods, and systems for beamforming using tunable passive time-delay structures are disclosed. One apparatus includes a node, wherein the node includes a passive time-delay structure, wherein the passive time-delay structure is operative to generate a plurality of delayed signals, wherein each of the plurality of delayed signals is a delayed version of a communication signal, a tunable element, the tunable element operative to introduce a variable delay to the communication signal propagating through the passive time-delay structure, an antenna array, wherein the antenna array generates a beamforming pattern corresponding the passive time-delay structure, and a phase delay adjust control operative to adjust the tunable element of the passive time-delay structure, wherein a direction of the one or more beams of the beamforming pattern changes depending upon tuning of the tunable element.

Systems and methods for closed loop MIMO (multiple input and multiple output) wireless communication are provided. Various transmit formats including spatial multiplexing and STTD are defined in which vector or matrix weighting is employed using information fed back from receivers. The feedback information may include channel matrix or SVD-based feedback.

Techniques for sending feedback information for multi-carrier operation are described. In an aspect, feedback information may be sent on an uplink carrier that may or may not be paired with a downlink carrier on which data transmission is sent. A user equipment (UE) may receive data transmission on a downlink carrier among a plurality of downlink carriers. The UE may determine feedback information for the data transmission, determine an uplink carrier to use to send the feedback information from among a plurality of uplink carriers, and send the feedback information on the uplink carrier. In another aspect, feedback information for multiple downlink carriers may be sent on at least one uplink carrier using Single-Carrier Frequency Division Multiple Access (SC-FDMA). A UE may receive data transmissions on a plurality of downlink carriers, determine feedback information for the data transmissions, and send the feedback information on at least one uplink carrier using SC-FDMA.

A method for X2 interface communication is disclosed, comprising: at an X2 gateway for communicating with, and coupled to, a first and a second radio access network (RAN), receiving messages from the first RAN according to a first X2 protocol and mapping the received messages to a second X2 protocol for transmission to the second RAN; maintaining state of one of the first RAN or the second RAN at the X2 gateway; executing executable code received at an interpreter at the X2 gateway as part of the received messages; altering the maintained state based on the executed executable code; and receiving and decoding an initial X2 message from the first RAN; identifying specific strings in the initial X2 message; matching the identified specific strings in a database of stored scripts; and performing a transformation on the initial X2 message, the transformation being retrieved from the database for stored scripts, the stored scripts being transformations.

A method and system are provided for scheduling data transmission in a Multiple-Input Multiple-Output (MIMO) system. The MIMO system may comprise at least one MIMO transmitter and at least one MIMO receiver. Feedback from one or more receivers may be used by a transmitter to improve quality, capacity, and scheduling in MIMO communication systems. The method may include generating or receiving information pertaining to a MIMO channel metric and information pertaining to a Channel Quality Indicator (CQI) in respect of a transmitted signal; and sending a next transmission to a receiver using a MIMO mode selected in accordance with the information pertaining to the MIMO channel metric, and an adaptive coding and modulation selected in accordance with the information pertaining to the CQI.

Techniques described herein describe aspects of signal adjustments in user equipment-coordination set, UECS, joint transmissions. A base station analyzes a first joint transmission from multiple user equipments, UEs, participating in a UECS, where the multiple UEs include a coordinating UE of the UECS and at least one non-coordinating UE participating in the UECS. The base station determines that the first joint transmission fails to meet a performance metric and directs the multiple UEs participating in the UECS to add signal adjustments to a second joint transmission.

The present disclosure relates to a pre-5.sup.th-Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4.sup.th-Generation (4G) communication system such as Long Term Evolution (LTE). The present invention provides a method and a device for cancelling inter-symbol interference in a wireless communication system. A method for a base station in a wireless communication system can comprises the steps of: transmitting multiple synchronous signals through multiple antennas to a terminal; receiving information on a propagation delay difference among the multiple synchronous signals from the terminal; and determining signal transmission timing for each of the multiple antennas on the basis of the information on the propagation delay difference.

Apparatuses, methods, and systems for beamforming using tunable passive time-delay structures are disclosed. One apparatus includes a node, wherein the node includes a passive time-delay structure, wherein the passive time-delay structure is operative to generate a plurality of delayed signals, wherein each of the plurality of delayed signals is a delayed version of a communication signal, a tunable element, the tunable element operative to introduce a variable delay to the communication signal propagating through the passive time-delay structure, an antenna array, wherein the antenna array generates a beamforming pattern corresponding the passive time-delay structure, and a phase delay adjust control operative to adjust the tunable element of the passive time-delay structure, wherein a direction of the one or more beams of the beamforming pattern changes depending upon tuning of the tunable element.