Patent classifications
H04L25/0232
Communication system determining time of arrival using matching pursuit
A wireless receiver receives location pilots embedded in received symbols and uses the location pilots to detect the first path for every base station the network has designated for the receiver to use in time of arrival estimation. The receiver preferably applies matching pursuit strategies to offer a robust and reliable identification of a channel impulse response's first path. The receiver may also receive and use estimation pilots as a supplement to the location pilot information in determining time of arrival. The receiver can use metrics characteristic of the channel to improve the robustness and reliability of the identification of a CIR's first path. With the first path identified, the receiver measures the time of arrival for signals from that path and the receiver determines the observed time difference of arrival (OTDOA) to respond to network requests for OTDOA and position determination measurements.
Channel acquistion using orthogonal time frequency space modulated pilot signal
Techniques for performing channel estimation in an orthogonal time, frequency and space (OTFS) communication system include receiving a wireless signal comprising a data signal portion and a pilot signal portion in which the pilot signal portion includes multiple pilot signals multiplexed together in the OTFS domain, performing two-dimensional channel estimation in a time-frequency domain based on a minimum mean square error (MMSE) optimization criterion, and recovering information bits using a channel estimate obtained from the two-dimensional channel estimation.
METHOD AND DEVICE FOR PERFORMING CHANNEL ESTIMATION
The method: extracts symbols at pilot positions from the received stream of symbols, estimates noise variances at pilot positions, determines a rough channel estimation from the symbols extracted at pilot positions, determines weighting coefficients from the estimated noise variances, weights the rough channel estimation by the determined weighting coefficients, filters the weighted rough channel estimation using predetermined coefficients, at least one predetermined coefficient being different from the other predetermined coefficients, the predetermined coefficients being determined for a constant noise variance, determines normalization coefficients from the determined weighting coefficients and predetermined filter coefficients, normalizes the filtered weighted rough channel estimation using the determined normalization coefficients.
ELECTRONIC DEVICE, METHOD AND APPARATUS FOR WIRELESS COMMUNICATION SYSTEM, AND STORAGE MEDIUM
An electronic device and method for wireless communication system, and a storage medium. In the method, reference signal are carried merely on a part of communication sources for channel estimation, channel states on the communication resources carrying the reference signal are estimated, and conditions of channel paths from a transmitter to a receiver are estimated by using the estimated channel states of the communication resources. Thereby, channel states on other communication resources from the transmitter to the receiver can be obtained from the estimated channel path conditions.
Orthogonal sequence based reference signal design for next generation WLANs
The present invention discloses methods and devices for communicating data in a Wireless Local Area Network (WLAN). An orthogonal frequency division multiplexing (OFDM) frame is communicated between an access point (AP) and a station (STA). The OFDM frame comprises a preamble section and a data payload section. The data payload section includes communication payload data and reference signal (RS) data pertaining to a wireless channel. The RS data comprises one of an orthogonal sequence-based reference signal (OSRS), a quasi-orthogonal sequence-based reference signal (QOSRS), and a tone interleaved long training field (TIL)-based RS.
Tracking Reference Signal And Framework Thereof In Mobile Communications
Techniques and examples of tracking reference signal and framework thereof in mobile communications are described. A user equipment (UE) receives, from a base station of a network, a reference signal via a communication link between the UE and the base station. The reference signal contains resource configuration with respect to tracking reference signal (TRS) configuration. The UE also receives, from the base station, a TRS burst containing a plurality of TRS symbols with one or more components of the UE configured according to the TRS configuration. The UE processes the TRS burst to perform channel estimation, synchronization, time tracking, frequency tracking, or a combination thereof.
Pilot symbol patterns for transmission through a plurality of antennas
A method and apparatus for improving channel estimation within an OFDM communication system. Channel estimation in OFDM is usually performed with the aid of pilot symbols. The pilot symbols are typically spaced in time and frequency. The set of frequencies and times at which pilot symbols are inserted is referred to as a pilot pattern. In some cases, the pilot pattern is a diagonal-shaped lattice, either regular or irregular. The method first interpolates in the direction of larger coherence (time or frequency). Using these measurements, the density of pilot symbols in the direction of faster change will be increased thereby improving channel estimation without increasing overhead. As such, the results of the first interpolating step can then be used to assist the interpolation in the dimension of smaller coherence (time or frequency).
Method for Low Voltage Broadband Power Line Carrier Communication
Disclosed is a method for low voltage broadband power line carrier communication; when transmitting a physical layer protocol frame, short preambles are first transmitted to undergo automatic gain control, channel estimation, coarse-grained frequency offset compensation, and symbol synchronization; and then long preambles are transmitted to undergo automatic gain control, channel estimation, fine-grained frequency offset compensation, and symbol synchronization. Compared with the scheme of only transmitting long preambles, the present disclosure combines transmissions of short preambles and long preambles, which thus may quickly and accurately implement frequency offset compensation, automatic gain control, symbol synchronization, and channel estimation without sacrifice of precision, thereby achieving quick convergence, reducing resource overheads and time overheads, and enhancing system performance.
Traveling pilots within single user, multiple user, multiple access, and/or MIMO wireless communications
Pilot tones are included within symbols (e.g., orthogonal frequency division multiplexing (OFDM) symbols) transmitted between wireless communication devices. The pilot tones occupy fewer than all tone locations in any given symbol, and the pilot tones occupy different respective locations within different symbols. Generally, these traveling pilots are assigned to different respective tone locations in different symbols. In total, the pilot tones did not cover every single tone location within the symbols used to convey information between devices. Considering for example, when pilots occupy fewer than all tone locations, even among multiple symbols, a device may perform interpolation to generate a pilot tone estimate corresponding to a tone location not occupied by pilot tone within any symbol. Also, power or magnitude of the pilot tones themselves may be boosted or amplified relative to power magnitude of other tones within such symbols.
Hybrid analog/digital equalizer architecture for high-speed receiver
Equalization circuitry for a data channel in an integrated circuit device includes an analog equalization stage coupled to the data channel, and a digital signal processing stage downstream of the analog equalization stage. The digital signal processing stage generates control signals to control the analog equalization stage, and includes a digital equalization stage that operates on output of the analog equalization stage. The analog equalization stage may further include an enhanced processing stage for optical signals, which may be selectably coupled to the analog equalization stage. The analog equalization stage may include at least one feed-forward or feedback equalization stage, and a decision stage that outputs decision signals at one of a first plurality of signal levels. The enhanced processing stage operates on the decision signals to output enhanced decision signals at one of a second plurality of signal levels of higher resolution than the first plurality of signal levels.