Patent classifications
H04B1/71072
TECHNIQUES FOR DETECTING AND CANCELLING INTERFERENCE IN WIRELESS COMMUNICATIONS
Various aspects described herein relate to cancelling interference in wireless communications. Energy level detection of a received signal can be performed to determine an allocation size and position corresponding to an interfering device in the received signal. An interference demodulation reference signal (DM-RS) and cyclic shift of the interfering device in the received signal can be determined. It can be determined whether to apply successive interference cancellation on the received signal, based at least in part on the allocation size and position and the DM-RS and cyclic shift, to cancel interference from the interfering device.
MULTIPLE ACCESS FOR USERS WITH DIFFERENT MODES IN A COMMON UPLINK BURST IN A TIME DIVISION DUPLEX SUBFRAME STRUCTURE
Various aspects of the present disclosure provide for methods, apparatus, and computer software for multiple access to a channel carrying a common uplink burst transmitted by users that utilize two different modes. Specifically, a coupled mode provides for range extension for users at a cell edge, while a decoupled mode provides for user data transmissions within the common uplink burst. Multiple access between these different modes may be provided in a non-orthogonal scheme by moderating the amount of interference between the respective modes. Further, multiple access between these different modes may be provided in an orthogonal scheme by utilizing interleaved frequency division multiple access (IFDMA).
User apparatus, base station, successive interference canceling process method, and successive interference canceling control method
A user apparatus for use in a radio communication system, including: an successive interference cancelling reception unit configured to obtain a desired signal by successively canceling an interference signal that becomes interference to the desired signal from a received signal that the user apparatus receives; and an ordering determination unit configured to determine an order of interference signals to be successively canceled by the successive interference cancelling reception unit, wherein the ordering determination unit determines the order based on reception quality for each interference signal.
MULTI-ANTENNA TRANSMISSION FOR SPATIAL DIVISION MULTIPLE ACCESS
An uplink channel response matrix is obtained for each terminal and decomposed to obtain a steering vector used by the terminal to transmit on the uplink. An effective uplink channel response vector is formed for each terminal based on its steering vector and its channel response matrix. Multiple sets of terminals are evaluated based on their effective channel response vectors to determine the best set (e.g., with highest overall throughput) for uplink transmission. Each selected terminal performs spatial processing on its data symbol stream with its steering vector and transmits its spatially processed data symbol stream to an access point. The multiple selected terminals simultaneously transmit their data symbol streams via their respective MIMO channels to the access point. The access point performs receiver spatial processing on its received symbol streams in accordance with a receiver spatial processing technique to recover the data symbol streams transmitted by the selected terminals.
APPARATUS AND METHOD FOR SIGNAL DETECTION IN A WIRELESS COMMUNICATION SYSTEM
An electronic device and method for signal detection in a wireless communication system is provided. The electronic device includes a receiving unit configured to receive a radio frequency (RF) signal, a control unit configured to process the received signal, wherein processing the received signal comprises canceling a signal corresponding to a first stage in the received signal, detecting a signal corresponding to a second stage by applying lattice reduction, and determining a final detected signal by combining the detected signal corresponding to the second stage with candidates of the signal corresponding to the first stage.
Method and system for symbol level interference cancellation at a receiver for multiuser detection
Methods and systems of symbol level interference cancellation at a receiver for multiuser detection is provided. In an embodiment, the method includes performing an interference cancellation based decoding for a plurality of users through a plurality of iterations for generating a plurality of soft bit estimates for each of the users during each of the iterations. Each of the iterations involves sequential cancellation of each of the user signals for performing interference cancellation based decoding for each subsequent user other than a first user. The method also includes re-using the generated plurality of soft bit estimates for performing each subsequent iteration of the interference cancellation based decoding of the plurality of users. A plurality of soft bit estimates associated with each user generated during an (N1).sup.th iteration is re-used during an N.sup.th iteration for the user, N being a whole number with a minimum value of 2.
Methods for estimation and interference suppression for signal processing
A receiver in a CDMA system comprises a front end processor that generates a combined signal per source. A symbol estimator processes the combined signal to produce symbol estimates. An S-Matrix Generation module refines these symbol estimates based on the sub channel symbol estimates. An interference canceller is configured for cancelling interference from at least one of the plurality of received signals for producing at least one interference-cancelled signal.
RADIO BASE STATION, USER TERMINAL AND RADIO COMMUNICATION METHOD
A radio base station that communicates with a user terminal, and has a control section that executes control so that signals are time-division-multiplexed over a first radio resource region where symbols are multiplexed at a rate equal to or below a Nyquist rate and a second radio resource region where symbols are multiplexed at a faster rate than the Nyquist rate. The radio base station also includes a transmission section that transmits the signals that are time-division-multiplexed in the first radio resource region and the second radio resource region, to the user terminal to reduce the interference against predetermined signals in a radio communication system in which Faster-Than-Nyquist (FTN) is used.
METHOD AND SYSTEM FOR SYMBOL LEVEL INTERFERENCE CANCELLATION AT A RECEIVER FOR MULTIUSER DETECTION
Methods and systems of symbol level interference cancellation at a receiver for multiuser detection is provided. In an embodiment, the method includes performing an interference cancellation based decoding for a plurality of users through a plurality of iterations for generating a plurality of soft bit estimates for each of the users during each of the iterations. Each of the iterations involves sequential cancellation of each of the user signals for performing interference cancellation based decoding for each subsequent user other than a first user. The method also includes re-using the generated plurality of soft bit estimates for performing each subsequent iteration of the interference cancellation based decoding of the plurality of users. A plurality of soft bit estimates associated with each user generated during an (N1).sup.th iteration is re-used during an N.sup.th iteration for the user, N being a whole number with a minimum value of 2.
Wireless communication apparatus and wireless communication method
In a capacity region of a multiple access channel which is a theoretical limit, a combination of transmission speeds that are equal between the channels is realized. A wireless communication apparatus receives first to third frames, which are sequentially transmitted. The second frame is transmitted at a head time different from that of the first and third frames, and the second frame receives a first signal which is temporally superposed to both the first and third frames. A replica signal of the first frame is generated based on the result obtained by demodulating the first frame, and a second signal which is obtained by canceling it from the first signal is generated. The second frame is demodulated by using the second signal, and the interference from the first frame in the second frame in the second signal is canceled, and the interference from the third frame remains.