Olympus Corporation

Siemens Communications, Inc.

Siemens Aktiengesellschaft

Siemens Information & Communication Mobile, LLC

Lichung Chu

Thomas Klingenbrunn

Antoine Jean Rouphael

Rongsheng Huang

Benny Vejlgaard

Shinhaeng Lee

Denis A Gudovskiy

Shigeyuki Shoda

Abu Amanullah

Dumitru Mihai Ionescu

Mohammad Nekoui

Ivan Krivokapic

Haidong Zhu

Benny Veilgaard

An improved sliding discrete Fourier transform (SDFT) algorithm called CIC-SDFT and its apparatus are provided. An input signal is multiplied by a modulated twiddle factor, and is then processed by a modified cascade integrator-comb (CIC) filter. The CIC-SDFT comprises an integrator section and a comb section, with a downsampler disposed between the two sections to enable downsampling of the SDFT computations. Through addition of more integrator stages and comb stages to the CIC-SDFT, the accuracy of spectrum estimation may be improved in a computationally inexpensive manner and with less complexity than applying windowing functions to known SDFTs. Various embodiments provide a partially-nonrecursive method of CIC-SDFT that further decreases computational complexity.

Method and apparatus for accurate and efficient spectrum estimation using improved sliding DFT

Systems and methods are provided in which a wireless receiver can be configured to digitally synchronize a receive sampling rate to a transmit sampling rate, and may include a digital interpolator controlled by a timing control unit with a timing offset estimator. The timing control unit can be configured to calculate and output parameters to the digital interpolator. The digital interpolator can include a sample buffer followed by a fractional delay filter. Output parameters to the digital interpolator can include a fractional delay timing offset signal of the receiver relative to a transmitter timing signal and a buffer pointer control signal to control a position of the read pointer relative to a write pointer to compensate for subsample timing offset. The timing offset estimator can be configured to calculate and provide to the timing control unit a sampling period ratio control word and an instantaneous timing offset control word.

Sampling rate synchronization between transmitters and receivers

Systems and methods are provided in which a wireless receiver can be configured to compensate frequency and phase offsets with joint symbol timing recovery of modulated signals transmitted across a channel, and it can include a transformation module configured to generate an error signal for an information signal representing the modulated signal received by the receiver. The transformation module can include a squaring module configured to square the information signal, thereby generating a squared signal, and a mixer configured to perform a complex multiplication of the squared signal by the local reference signal, and a downsampler. The transformation module can also be configured to extract and compensate frequency and phase offsets with joint symbol timing recovery.

Frequency and phase offset compensation of modulated signals with symbol timing recovery

Body area networks (BANs) implemented in accordance with this disclosure may enter a disaster rescue mode. The disaster rescue mode is triggered in disaster scenarios to help body devices to assist in rescue.

Disaster rescue mode for body area networks

A time division multiple access (TDMA) media access control (MAC) protocol is provided for wireless body area networks (BANs). In particular, in some embodiments the described network devices utilize signaling to modify previously made reservations. In other embodiments, reservation adjustment is performed without using signaling. Preemption can also be used to allow flexible reservation adjustment.

Flexible reservation-based MAC for wireless body area networks

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.

Method and system for group management

A time division multiple access (TDMA) media access control (MAC) protocol is provided for wireless body area networks (BANs). In particular, in some embodiments the described network devices utilize a reservation-based power saving polling (RESP) MAC protocol for communication. The RESP MAC can be configured to provide methods for emergency event handling of both bursty data and streaming data.

Power-saving hub messages in wireless body area networks

Allocation slot arrangement is provided for wireless body area networks (BANs). In particular, in some embodiments the allocation slots are arranged based on a set of rules and received input parameters. Allocation slot arrangement may comprise maximizing a weighted sum function computed by applying the rules and input parameters to all nodes over all possible arrangements.

Allocation slot arrangement for wireless body area networks with sensor initiated grant extensions

Power-saving TDMA MAC for wireless body area networks

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.

Low-power narrow and wide band receiver system

A tap-selectable Viterbi equalizer comprises means for determining at least one symbol from a previous determination assigned to a first state, means for determining a second state of the plurality of states and determining a surviving path metric by comparing path metrics originating from the determined symbol, means for determining the value of a previous symbol with respect to the symbol of the surviving state, and calculating means for generating a reduced trellis by calculating only path metrics for states in which the previous symbol has the determined value.

Tap-selectable viterbi equalizer

A digital arrangement for selecting a channel coefficient and DC estimate comprises a demultiplexer receiving a digital input signal splitting the digital input signal into a first and second signal, a first joint detection unit receiving the first signal generating a first channel coefficient and DC estimate, a second joint detection unit receiving the second signal generating a second channel coefficient and DC estimate, a first and second error determination unit receiving the first and second channel coefficients and DC estimates, respectively for generating a first and second error signal, a decision unit receiving the first and second error signals generating a control signal, and a selection unit controlled by the control signal for selecting the first or second channel coefficient and DC estimate.

Arrangement for dynamic DC offset compensation

A DC tracking arrangement includes a first tracking unit for slow tracking receiving an input signal and generating a first output signal, a second tracking unit for fast tracking receiving the input signal and generating a second output signal, and a decision unit receiving the first and second output signal for selecting the first or second output signal.

A method of processing a sequence of digital symbols comprises the steps of processing the sequence of digital symbols and determining an uncertainty in the processing. If the uncertainty exceeds a predetermined threshold, then the method further comprises the steps of processing at least two sequences of digital symbols wherein at least one parameter is set differently in each sequence, and deciding upon a calculated error for each sequence which sequence is used to generate an output signal.

Multilevel decision feedback equalizer

A digital signal detector arrangement comprises at least two selectable baseband filters for receiving a digital signal, a signal estimator receiving the output signal of the selected baseband filter, a modulator unit receiving the estimated signal from the signal estimator, a subtractor for subtracting the modulated signal from the received digital signal, and a determination unit receiving the signal from the subtractor for selecting the baseband filter.

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San Diego, CA, United States of America

Lichung Chu