Patent classifications
H04L7/08
Method and apparatus for time synchronisation in wireless networks
A wireless media distribution system is provided comprising an access point (6) for broadcasting media and a plurality of stations (2) for reception and playback of media. Each station is configured for receiving and decoding a timestamp in a beacon frame transmitted repeatedly from the access point. This is used to control the output signal of a station physical layer clock (12) which is then used as a clock source for an application layer time synchronisation protocol. This application layer time synchronisation protocol can then be used in the station to control an operating system clock (8) for regulating playback of media.
Low power long-range radio
Advanced modulation and demodulation schemes for LoRa or equivalent chirp spread spectrum transmissions, with differential modulation and symbol repetition improve the sensitivity in combination with soft demodulation methods.
Low power long-range radio
Advanced modulation and demodulation schemes for LoRa or equivalent chirp spread spectrum transmissions, with differential modulation and symbol repetition improve the sensitivity in combination with soft demodulation methods.
Method and apparatus for detection of boundary between transmission and reception in TDD communication systems
In many wireless communication systems, there is a major problem with the coverage in indoor environments because of signal loss during signal penetration through walls and other structures. Femto cells or repeaters may be used to address the signal coverage issue for indoor environments. The cost of femto cells or repeaters may be high depending on its capabilities. Method and apparatus are disclosed for a Signal Enhancer with reduced complexity to enhance the signal for an OFDM based TDD wireless communication system. This may result in a lower cost solution for improving the coverage and the overall communication system performance.
SYSTEM AND METHOD FOR WIDE-BAND ADAPTIVE EQUALIZATION AND EYE OPENING MONITORING WITH LINK QUALITY DETECTION
A method for assessing link quality includes detecting an eye opening of a transmission link. The detected eye opening of the transmission link is compared with a threshold eye opening or at least one previously detected eye opening. A link quality of the transmission link is assessed based upon a comparison of the eye opening with the threshold eye opening or the at least one previously detected eye opening.
SYSTEM AND METHOD FOR WIDE-BAND ADAPTIVE EQUALIZATION AND EYE OPENING MONITORING WITH LINK QUALITY DETECTION
A method for assessing link quality includes detecting an eye opening of a transmission link. The detected eye opening of the transmission link is compared with a threshold eye opening or at least one previously detected eye opening. A link quality of the transmission link is assessed based upon a comparison of the eye opening with the threshold eye opening or the at least one previously detected eye opening.
TIME DOMAIN PILOT OF SINGLE-CARRIER MIMO SYSTEM AND SYNCHRONIZATION METHOD THEREOF
The present invention discloses a time domain pilot design solution suitable for a single-carrier MIMO system. The design solution comprises a time domain pilot location design and a training sequence design. In the present invention, several identical ZCZ sequences are uniformly inserted into each of the data blocks in the same data stream to serve as training sequences, wherein the training sequences inserted into different data streams are different. In addition, the present invention also discloses a simple algorithm for pilot tracking and phase correction suitable for the time domain pilot design solution for the single-carrier MIMO system. The time domain pilot design solution for a single-carrier MIMO system and the algorithm for pilot tracking and phase correction as disclosed in the present invention can improve the performance of a system.
TIME DOMAIN PILOT OF SINGLE-CARRIER MIMO SYSTEM AND SYNCHRONIZATION METHOD THEREOF
The present invention discloses a time domain pilot design solution suitable for a single-carrier MIMO system. The design solution comprises a time domain pilot location design and a training sequence design. In the present invention, several identical ZCZ sequences are uniformly inserted into each of the data blocks in the same data stream to serve as training sequences, wherein the training sequences inserted into different data streams are different. In addition, the present invention also discloses a simple algorithm for pilot tracking and phase correction suitable for the time domain pilot design solution for the single-carrier MIMO system. The time domain pilot design solution for a single-carrier MIMO system and the algorithm for pilot tracking and phase correction as disclosed in the present invention can improve the performance of a system.
ENABLING A PERFORMANCE MEASUREMENT IN A PACKET-SWITCHED COMMUNICATION NETWORK
A method for enabling a performance measurement on packet flow transmitted through a communication network. A marking value is periodically switched in the packets with a marking period Tm. The packet flow is then divided into blocks of duration Ts (synchronization period). Each synchronization period comprises an integer number of marking periods. Two or more measurement points on the path of the packet flow may provide a performance parameter for each marking period and associate thereto a synchronization information generated based on their local clocks and relating to the synchronization period containing the marking period to which the performance parameter relates; and a sequence information indicating the marking period's position within the synchronization period. A management server may identify performance parameters provided by different measurement points and relating to a same marking period based on the synchronization information and the sequence information.
METHODS FOR NANOSECOND-SCALE TIME SYNCHRONIZATION OVER A NETWORK
A method includes, at a first node: transmitting a first synchronization signal at a first time according to a first clock of the first node; back-coupling the first synchronization signal to generate a first self-receive signal; calculating a time-of-arrival of the first self-receive signal according to the first clock; and calculating a time-of-arrival of the second synchronization signal according to the first clock. The method also includes, at the second node: transmitting the second synchronization signal at a second time according to a second clock of the second node; back-coupling the second synchronization signal to generate a second self-receive signal; calculating a time-of-arrival of the second self-receive signal according to the second clock; and calculating a time-of-arrival of the first synchronization signal according to the second clock. The method S100 further includes calculating a time bias and a propagation delay between the pair of nodes based on the time-of-arrivals.