Methods and systems for transmitting uplink control information and feedback are disclosed for carrier aggregation systems. A user equipment device may be configured to transmit uplink control information and other feedback for several downlink component carriers using one or more uplink component carriers. The user equipment device may be configured to transmit such data using a physical uplink control channel rather than a physical uplink shared channel. The user equipment device may be configured to determine the uplink control information and feedback data that is to be transmitted, the physical uplink control channel resources to be used to transmit the uplink control information and feedback data, and how the uplink control information and feedback data may be transmitted over the physical uplink control channel.

Uplink control data transmission

Channel state information is reported in periodic and aperiodic reports for multiple component carriers or serving cells Channel state information may be reported for a subset of aggregated downlink carriers or serving cells For an aperiodic report, the carrier(s)/serving cell(s) for which channel state information is reported are determined based on the request for the aperiodic report When a CQI/PMI/RI report and a HARQ ACK/NACK report coincide in a subframe, the HARQ ACK/NACK report is transmitted on PUCCH, and the CQI/PMI/RI report is transmitted on PUSCH

Channel state information transmission for multiple carriers

A method for transmitting a signal via physical uplink control channel (PUCCH) in a wireless communication system and an apparatus for performing the method are provided. Control information bits are modulated to generate N1 modulation symbols, wherein N1 is twice a number of subcarriers in one resource block (RB). The modulation symbols are spread by using various orthogonal codes to generate a plurality of sequences and the generated plurality of sequences are transmitted using different slots of a subframe through different antenna ports, each sequence of the plurality of sequences being mapped on a corresponding single carrier frequency division multiple access symbol in a corresponding slot.

Method and apparatus for transmitting control information in a wireless communication system

A system and method are described which enable planned evolution and obsolescence of multiuser wireless spectrum. One embodiment of such a system includes one or multiple centralized processors and one or multiple distributed nodes that communicate via wireline or wireless connections. The distributed nodes may share their identification number and other reconfigurable system parameters with the centralized processor. The information about all distributed nodes may be stored in a database that is shared by all centralized processors. The reconfigurable system parameters may comprise power emission, frequency band, modulation/coding scheme. The distributed nodes may be software defined radios such as FPGA, DSP, GPU and/or GPCPU that run algorithms for baseband signal processing and may be reconfigured remotely by the centralized processor. A cloud wireless system may be used wherein the distributed nodes are reconfigured periodically or instantly to adjust to the evolving wireless architecture.

System and methods for planned evolution and obsolescence of multiuser spectrum

A system and methods are described which compensate for the adverse effect of Doppler on the performance of DIDO systems. One embodiment of such a system employs different selection algorithms to adaptively adjust the active BTSs to different UEs based by tracking the changing channel conditions. Another embodiment utilizes channel prediction to estimate the future CSI or DIDO precoding weights, thereby eliminating errors due to outdated CSI.

System and methods to compensate for Doppler effects in multi-user (MU) multiple antenna systems (MAS)

Precoding for multiple transmission streams in multiple antenna systems. Embodiments herein disclose a general method that transmits signal from multiple antennas using a one/two dimensional precoder followed by STBC/SFBC or SM encoder. This precoder is fixed in a given resource block (RB) or slot, which is composed of P subcarriers and Q OFDM symbols (where the values for P and Q are greater than or 5 equal to 1). The precoder in each resource block may take same or different values, which span the two dimensional time-frequency grid. The precoder is chosen as a function of either logical frequency index or physical frequency index of the RB.

Precoding for single transmission streams in multiple antenna systems

Embodiments disclosed herein reduce interference at pilot symbols and also enable good interference measurements by using a combination pilot tones and null tones along with null tones. In this type of system, the receivers can estimate tile channel state information without any interference from the remaining transmitters and at the same time the receiver can measure either the individual interference channel states or the interference covariances from the silent periods. The groups of transmitters are reused in geographically separated region using a frequency reuse structure. In a preferred implementation, pilot signal is precoded using a multi-antenna precoder. The precoder may be same for pilot and data.

Pilot aided data transmission and reception with interference mitigation in wireless systems

Embodiments herein provide methods and systems for enhancing interference mitigation using conjugate symbol repetition and phase randomization on a set of subcarriers. The repeated data tone in the signal is complex-conjugated before transmission, when the repetition factor is two. When the repetition factor is greater than two, a combination of conjugate repetition and random/deterministic phase variation of the repeated tones is used to mitigate the interference mitigation. Embodiments further disclose Collision Free Interlaced Pilot PRU Structures that can be used with or without conjugate symbol repetition and phase randomization for interference mitigation.

Methods and systems for interference mitigation

Ever since the adoption of the single carrier frequency division multiple access (SC-FDMA) scheme for the uplink in the Long Term Evolution (LTE) standard, there has been much interest in improved receiver algorithms for the same. Successive interference cancelation (SIC) based turbo receivers (Turbo SIC) have been proposed to tackle the multi-stream interference (MSI) for transmission modes such as spatial multiplexing (SM) and multiuser (MU) multiple input multiple output (MIMO). In addition, decision feedback equalizers (DFE) have been discussed as an alternative to the simple linear minimum mean square error (LMMSE) based receivers to suppress intersymbol interference (ISI) caused by the frequency selective multi-path channel. This paper proposes a DFE receiver variant based on parallel interference cancelation (PIC) with maximum likelihood detection (MLD) and ordered SIC (OSIC) principles to suppress ISI and MSI. Simulations show that the proposed receiver performs better than the existing SIC and DFE based receivers and achieves the matched filter bound (MFB) for both coded and uncoded systems.

An Iterative DFE Receiver for MIMO SC-FDMA Uplink

Embodiments herein disclose a digitally precoded SC-FDMA scheme with low PAPR, where the scheme applies a constellation rotation to the M-ary input data sequence, before circularly convolving the rotated data sequence with a polynomial decoder. The data is then transformed to the frequency domain and then mapped. An N-point IIFT is then applied to the data to produce time domain samples.

Baskaran Dhivagar

Papers

Precoding for single transmission streams in multiple antenna systems

Pilot aided data transmission and reception with interference mitigation in wireless systems

Methods and systems for interference mitigation

An Iterative DFE Receiver for MIMO SC-FDMA Uplink

Method and system for signal transmission and reception