摘要:
A communications device and receiver system and method to efficiently distribute functions among radio frequency (RF), analog front end (AFE) and baseband modules for ultra-low power consumption comprising a wideband receiver subsystem selectively coupled to a signal input receiving a first frequency band, a narrowband received subsystem selectively coupled to the signal input receiving a second frequency band and, a controller configured to monitor the first frequency band using the first receiver subsystem and if a wake up signal is detected using the first receiver subsystem, connect the second receiver subsystem to the signal input and tune the second receiver subsystem to a channel transmitting the wake up signal, the wake up signal including channel selection information defining the channel for subsequent communications. Wherein, the two frequency bands overlap and center on different frequencies.
摘要:
Systems and methods for group management in machine-to-machine networks are provided. Network nodes in a network group are divided into sub-groups and a group information register, which includes a listing of the nodes in the group, is divided into an equal number of partitions. The partitions are distributed to the sub-groups such that each node in a given sub-group receives the same partition. The partitions are accompanied by references to network nodes of other sub-groups (termed “anchor nodes”) that have a copy of another partition of the group information register. When a new network head takes over the network group, it is able to use the available partitions to determine which partitions are missing and which nodes hold copies of the missing partitions. The group head can wake up the missing nodes and obtain the missing partition copies, thereby generating a complete copy of the group information register.
摘要:
A method for determining an overlap and add length estimate comprises determining a plurality of correlation values of a plurality of ordered frequency domain samples obtained from a data frame; comparing the correlation values of a first subset of the samples to a first predetermined threshold to determine a first edge sample; comparing the correlation values of a second subset of the samples to a second predetermined threshold to determine a second edge sample; using the first and second edge samples to determine an overlap and add length estimate; and providing the overlap and add length estimate to an overlap and add circuit.
摘要:
Phase tracking in an OFDM symbol comprises determining a sufficient statistic for CFO and SFO estimation from a differential metric between a current OFDM symbol and a previous OFDM symbol transmitted on the same frequency band. The sufficient statistics corresponding to positive pilot tones are combined with those corresponding to negative pilot tones to estimate the CFO and SFO.
摘要:
A master device selects a channel from a band of channels for communications with a slave device. The master transmits information identifying the selected to the slave device using a packet modulated as a series of energy pulses on the selected channel. The slave device performs wideband energy detection on the band of channels and receives the modulated pulses. The slave device decodes the modulated pulses to retrieve the selected channel, and tunes to the selected channel for further communications.
摘要:
Various embodiments of the systems and methods described herein may be used to compute a minimum variance unbiased estimator by receiving a first OFDM signal at a pilot tone, receiving a second OFDM signal sent in the same frequency band and determining a differential phase metric between the first OFDM signal and the second OFDM signal. In some embodiments, the differential phase metric may be used to diversity combine synchronization statistics. In various embodiments, the differential phase metric may be used to detect a narrow-band interference.
摘要:
Various embodiments of the systems and methods described herein may be used to compute a minimum variance unbiased estimator by receiving a first OFDM signal at a pilot tone, receiving a second OFDM signal sent in the same frequency band and determining a differential phase metric between the first OFDM signal and the second OFDM signal. In some embodiments, the differential phase metric may be used to diversity combine synchronization statistics. In various embodiments, the differential phase metric may be used to detect a narrow-band interference.
摘要:
The present invention is directed to a system and method for channel estimation for a communication channel such as, for example, that found in a wireless communication network. One or more synchronization and channel estimate symbols can be combined to compute a refined channel estimate.
摘要:
Various embodiments of the systems and methods described herein may be used to compute a minimum variance unbiased estimator by receiving a first OFDM signal at a pilot tone, receiving a second OFDM signal sent in the same frequency band and determining a differential phase metric between the first OFDM signal and the second OFDM signal. In some embodiments, the differential phase metric may be used to diversity combine synchronization statistics. In various embodiments, the differential phase metric may be used to detect a narrow-band interference.
摘要:
Various embodiments of the systems and methods described herein may be used to compute a minimum variance unbiased estimator by receiving a first OFDM signal at a pilot tone, receiving a second OFDM signal sent in the same frequency band and determining a differential phase metric between the first OFDM signal and the second OFDM signal. In some embodiments, the differential phase metric may be used to diversity combine synchronization statistics. In various embodiments, the differential phase metric may be used to detect a narrow-band interference.