Qualcomm Incorporated

Senomyx, Inc.

Mark S Wallace

Steven J Howard

John Wendell Ketchum

Jay Rodney Walton

J Rodney Walton

Jay Rod Walton

Fuyun Ling

Ahmad Jalali

Irina Medvedev

John Edward Smee

Lizhong Zheng

Sanjiv Nanda

Franklin Peter Antonio

Edward George Tiedemann, Jr

Stein Arne Lundby

Jack M Holtzman

Murali Paravath Menon

Peter S Gaal

Naga Bhushan

Charles E Wheatley, Iii

Nagabhushana T Sindhushayana

Xiangdong Zhang

Rajat Prakash

Jun Ma

Luca Blessent

Qiang Wu

Andrei Dragos Radulescu

Yu-Cheun Jou

Rashid Ahmed Attar

Mark Zoller

Catherine Tachdjian

Srikant Jayaraman

Guy Servant

Vincent Darmohusodo

Qing Chen

Andrew P Patron

Lei Xiao

Puay Hoe See

Evgeny Levitan

Xiao-Qing Tang

Shravan K Surineni

Farid Bakir

Xiadong Li

Ivan Jesus Fernandez Corbaton

Mohamad Sayed Hassan

Sara L Adamski-Werner

J Rodney Walton, Jr

Marketa Rinnova

Amy Xing

Peter Monsen

Ivan Fernandez

Hakan Inanoglu

Christian Oliver Thelen

Abhishek Saurabh Sachidanand Sinha

Daniel Harry Rogers

Michael Francis Garyantes

Stephen Terrence Hobson

Bjorn Bjerke

Afshin Shiravi

Sriram Narayan

Murali Menon

Klaus Gubernator

Jigneshkumar P Shah

Rod J Walton

Edward G Tiedemann

J Rod Walton

Ori Auslender

Leon Metreaud

Jay R Walton, Jr

Xiandong Zhang

Irena Medvedev

Irina c/o Qualcomm Incorporated Medvedev

Funyun Ling

Rodney J Walton

Ming Cai Lun Lu Qi

JRodney Walton

Jay R c/o Qualcomm Inc Walton

Charles E Iii Wheatley

Rod J Waltson

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a radio unit (RU) may receive, from a user equipment (UE), a demodulation reference signal (DMRS) associated with a channel. The RU may perform a channel estimation associated with the channel using the DMRS to obtain channel estimation information. The RU may transmit, to a distributed unit (DU), information that is based at least in part on the channel estimation information. Numerous other aspects are described.

Enhanced fronthaul interface split using demodulation reference signal channel estimates

Methods, systems, and devices for wireless communications are described. A wireless device may identify channel responses between antenna elements of antenna arrays of the wireless device and user equipments (UEs) at geographic locations within a coverage area of the wireless device. For example, the wireless device may identify the channel responses based on reference signal transmissions between the UEs and the wireless device. The wireless device may process the channel responses to identify one or more directional power peaks associated with the reference signal transmissions. The wireless device may, based on the one or more directional power peaks, detect phase error values, amplitude error values, or both common to the channel responses. The wireless device may adjust the signal communicated via at least a subset of the antenna elements based on the phase error values, the amplitude error values, or both and communicate with one or more of the UEs.

Antenna element calibration algorithm

This disclosure provides systems, methods and apparatuses for protecting against transmit power violations in a radio unit (RU) of a disaggregated base station. For example, when a distributed unit (DU) provides frequency domain samples to the RU, the DU may set a reference input level that causes the RU scale a gain lineup to avoid saturation or sensitivity issues in a signal processing chain while ramping up to a required transmit power. Accordingly, to avoid signal saturation or clipping at the RU, the RU may monitor energy estimation measurements and take remedial action when a transmit power violation occurs. For example, the RU may provide one or more system alarms to the DU or prevent transmission over an air interface in cases where the energy estimation measurements fail to satisfy one or more thresholds.

Transmit power violation protection mechanism in a radio unit of a disaggregated base station

Spatial spreading is performed in a multi-antenna system to randomize an 'effective' channel observed by a receiving entity for each transmitted data symbol block. For a MIMO system, at a transmitting entity, data is processed (e.g., encoded, interleaved, and modulated) to obtain Ndata symbol blocks to be transmitted in Ntransmission spans, where N&#x2265;1 and N&#x3e;1. The Nblocks are partitioned into Ndata symbol subblocks, one subblock for each transmission span. A steering matrix is selected (e.g., in a deterministic or pseudo-random manner from among a set of L steering matrices, where L&#x3e;1) for each subblock. Each data symbol subblock is spatially processed with the steering matrix selected for that subblock to obtain transmit symbols, which are further processed and transmitted via Ntransmit antennas in one transmission span. The Ndata symbol blocks are thus spatially processed with Nsteering matrices and observe an ensemble of channels.

Spatial spreading in a multi-antenna communication system

Pilots suitable for use in MIMO systems and capable of supporting various functions are described. The various types of pilot include&#x2014;a beacon pilot, a MIMO pilot, a steered reference or steered pilot, and a carrier pilot. The beacon pilot is transmitted from all transmit antennas and may be used for timing and frequency acquisition. The MIMO pilot is transmitted from all transmit antennas but is covered with different orthogonal codes assigned to the transmit antennas. The MIMO pilot may be used for channel estimation. The steered reference is transmitted on specific eigenmodes of a MIMO channel and is user terminal specific. The steered reference may be used for channel estimation. The carrier pilot may be transmitted on designated subbands/antennas and may be used for phase tracking of a carrier signal. Various pilot transmission schemes may be devised based on different combinations of these various types of pilot.

Pilots for MIMO communication systems

Transmitter and receiver units for use in an OFDM communications system and configurable to support multiple types of services. The transmitter unit includes one or more encoders, a symbol mapping element, and a modulator. Each encoder receives and codes a respective channel data stream to generate a corresponding coded data stream. The symbol mapping element receives and maps data from the coded data streams to generate modulation symbol vectors, with each modulation symbol vector including a set of data values used to modulate a set of tones to generate an OFDM symbol. The modulator modulates the modulation symbol vectors to provide a modulated signal suitable for transmission. The data from each coded data stream is mapped to a respective set of one or more 'circuits'. Each circuit can be defined to include a number of tones from a number of OFDM symbols, a number of tones from a single OFDM symbol, all tones from one or more OFDM symbols, or some other combination of tones. The circuits can have equal size or different sizes. Different circuits can be used for full rate data (e.g., active speech) and low rate data (e.g., silence periods).

Multiplexing of real time services and non-real time services for OFDM systems

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.

Multi-antenna transmission for spatial division multiple access

Coding techniques for a (e.g., OFDM) communication system capable of transmitting data on a number of 'transmission channels' at different information bit rates based on the channels' achieved SNR. A base code is used in combination with common or variable puncturing to achieve different coding rates required by the transmission channels. The data (i.e., information bits) for a data transmission is encoded with the base code, and the coded bits for each channel (or group of channels with the similar transmission capabilities) are punctured to achieve the required coding rate. The coded bits may be interleaved (e.g., to combat fading and remove correlation between coded bits in each modulation symbol) prior to puncturing. The unpunctured coded bits are grouped into non-binary symbols and mapped to modulation symbols (e.g., using Gray mapping). The modulation symbol may be 'pre-conditioned' and prior to transmission.

Coding scheme for a wireless communication system

Spatial spreading is performed in a multi-antenna system to randomize an 'effective' channel observed by a receiving entity for each transmitted data symbol block. For a MIMO system, at a transmitting entity, data is processed (e.g., encoded, interleaved, and modulated) to obtain Ndata symbol blocks to be transmitted in Ntransmission spans, where N&#x2267;1 and N&#x3e;1. The Nblocks are partitioned into Ndata symbol subblocks, one subblock for each transmission span. A steering matrix is selected (e.g., in a deterministic or pseudo-random manner from among a set of L steering matrices, where L&#x3e;1) for each subblock. Each data symbol subblock is spatially processed with the steering matrix selected for that subblock to obtain transmit symbols, which are further processed and transmitted via Ntransmit antennas in one transmission span. The Ndata symbol blocks are thus spatially processed with Nsteering matrices and observe an ensemble of channels.

Techniques for detecting and demodulating a signal/transmission are described. Signal detection is performed in multiple stages using different types of signal processing, e.g., using time-domain correlation for a first stage, frequency-domain processing for a second stage, and time-domain processing for a third stage. For the first stage, products of symbols are generated for at least two different delays, correlation between the products for each delay and known values is performed, and correlation results for all delays are combined and used to declare the presence of a signal. For demodulation, the timing of input samples is adjusted to obtain timing-adjusted samples. A frequency offset is estimated and removed from the timing-adjusted samples to obtain frequency-corrected samples, which are processed with a channel estimate to obtain detected symbols. The phases of the detected symbols are corrected to obtain phase-corrected symbols, which are demodulated, deinterleaved, and decoded.

Receiver for wireless communication network with extended range

Growing community of inventors

Bedford, MA, United States of America

Mark S Wallace