Silicon Laboratories Inc.

Hach Company

Hydrolab Corporation

Silicom Laboratories Inc.

Terry Lee Dickey

Yan Zhou

Wentao Li

Jeffrey A Tindle

Attila Zólomy

Mustafa H Koroglu

Vitor Pereira

Ádám Süle

Gerald D Champagne

Brian Mirkin

Michael Wu

Rangakrishnan Srinivasan

Sauli Johannes Lehtimaki

Joel Kauppo

Christopher L McCrank

Jesse Ira Masters

Donald Miner Markuson

Adám Süle

Micah Solomon Evans

Szabolcs Lõrincz

Hendricus De Ruijter

Ramin Khoini-Poorfard

Attila Zolomy

Pasi Rahikkala

Francesco Barale

Arup Mukherji

Zhongda Wang

John Robert Woodward

Wenhuan Yu

Mika Tapio Länsirinne

Praveen Vangala

Karl Lewis King

Gregory S Retzlaff

Jason Christopher Rock

Tamas Bodi

Tibor Herman

Andrea Nagy

Michael Albert Alkier

Daniel Simon

Kiruba Sankaran Subramani

Marius Munder

Bryan Murawski

Hendricus DeRuijter

A technique for adding a new information rate to a legacy physical interface of a communications system includes using a rate switch packet including a distinct rate select start-of-frame delimiter that indicates a newly defined physical interface packet. The rate switch packet uses the same modulation scheme as a base rate packet (e.g., a packet using an information rate defined by a standard communications protocol) and the same preamble pattern as the base rate packet. The preamble length of the rate switch packet can be the same as or different from the preamble length of the base rate packet. An embodiment uses antenna diversity by selecting the antenna in the rate switch packet and using the selected antenna to receive an adjusted rate packet. Additional rate switch start-of-frame delimiters can be used to indicate more than one adjusted rate packet, e.g., to support multiple adjusted information rates.

Method to add additional data rate to legacy physical interface

A demodulator has a correlator bank with multiple correlators. The correlator bank has multiple configurations, including a signal arrival configuration, a coarse timing configuration, and a despreading configuration. The various configurations are used to correlate function transformations of received symbols to template signals. Each correlator has elements with a number of delay blocks corresponding to a number of chips in a symbol. The output of each delay block is multiplied by a bit of a template signal by negating or not negating the output and the multiplications results are summed. A function transformations block receives phase information to generate the function transformations, which are supplied to the correlators. The function transformations include a transformation with a one chip differential, transformations with multi-chip differentials, an average transformation that includes an average of a one-chip phase difference between two adjacent samples, and a second order phase differentiation used for frequency deviation correlation.

Configurable correlator bank for a non-coherent DSSS demodulator

A printed circuit board having an AoX antenna array and a feeding circuit is disclosed. The AoX antenna array has patch antenna disposed on a top layer of the printed circuit board, while the feeding circuit is disposed on the bottom layer. The signal traces that connect the ports of the antenna unit cells to the antenna selection switches are routed so that all are roughly equal in length with a minimal length of parallel sections between signal traces. Thus, the signal traces in the feeding circuit are created so as to minimize phase difference between signal traces and to minimize coupling. Coplanar waveguides, which utilize blind vias are used to further reduce coupling.

Feeding circuit layout for 4 x 4 linear AoX arrays

A system and method for determine the spatial position of a network device is disclosed. A locator device having an antenna array is used to perform an AoX calculation to find the direction to the network device. The AoX calculation utilizes a plurality of the antennas in the antenna array. The locator device also performs a high accuracy distance measurement (HADM). In certain embodiments, only one antenna in the antenna array is used for the HADM calculation. Using the direction and the distance to the network device, the locator is able to determine the spatial position of the network device. In some embodiments, the antenna array may a rotational symmetry array having a plurality of outer antenna elements and one central antenna element.

Hybrid AoX and HADM system for low cost and simple location finding

A receiver includes a demodulator having a configurable correlator bank that helps with fast and robust signal detection. The demodulator detects arrival of a first preamble symbol using a first correlator bank configuration. The demodulator makes a course coarse frequency offset estimation after detection of the first preamble signal and the receiver adjusts a frequency used by a mixer based on the coarse frequency offset estimation. The demodulator confirms signal arrival detection with detection of a second preamble symbol. A coarse timing estimation is generated using a second correlator bank configuration using a multi-symbol observation period. A fine frequency offset estimation is made using a third correlation bank configuration. A fine timing estimation is made using a fourth correlation bank configuration. The demodulator then despreads received symbols using a fifth correlator bank configuration.

Non-coherent DSSS demodulator with fast signal arrival detection and improved timing and frequency offset estimation

A wireless communication device has a receiver to listen to a sequence of channels. A controller responds to a preamble being detected on a first channel while the receiver is tuned to the first channel by causing the receiver to stay on the first channel and decode packet(s) associated with the preamble. The controller responds to detection of a first symbol of a first transmission protocol and the preamble not being detected to cause the receiver to stay on the first channel for a predetermined time waiting for a retry. The controller responds to detection of a second symbol of a second transmission protocol and the preamble not being detected to cause the receiver to switch to an advertising channel of the second transmission protocol. If no preambles, noise, or symbols are detected, the receiver switches to listening to a next channel in the sequence after a fixed time.

Concurrent listening

A system and method for selecting a polarization for a particular antenna in an antenna array is disclosed. The system comprises an antenna array, wherein each antenna is adapted to receive and transmit horizontally and vertically polarized signals. The system also includes a switching network that is adapted to select the vertical or horizontal polarized signal for each antenna in the antenna array. The switching network also allows selection of a circular polarized signal from one or more of the antenna elements in the antenna array. This allows the AoX to be more accurate, as it is able to receive horizontally and vertically polarized signals, rather than just circular polarized signals, thereby improving its accuracy. The ability to receive circular polarized signals may be beneficial during reference periods to acquire the proper gain and frequency.

Antenna array with selectable horizontal, vertical or circular polarization

An antenna array that utilizes ground guard rings and metamaterial structures is disclosed. In certain embodiments, the antenna array is constructed from a plurality of antenna unit cells, wherein each antenna unit cell is identical. The antenna unit cell comprises a top surface, that contains a patch antenna and a ground guard ring. A reactive impedance surface (RIS) layer is disposed beneath the top surface and contains the metamaterial structures. The metamaterial structures are configured to present an inductance to the patch antennas, thereby allowing the patch antennas to be smaller than would otherwise be possible. In some embodiments, the metamaterial structures comprise hollow square frames. An antenna array constructed using this antenna unit cell has less coupling than conventional antenna arrays, which results in better performance. A ground skirt surrounds the perimeter of the antenna array to improve radiation phase pattern balance within the array.

Metamaterial antenna array with isolated antennas and ground skirt along the perimeter

A wireless transceiver including a receiver circuit coupled to an RF transceiver node, a tunable notch filter coupled between the RF transceiver node and a reference node, and a controller that programs the tunable notch filter with a selected blocker frequency and that selectively enables the tunable notch filter to attenuate at least one blocker signal. The tunable notch filter may include a variable capacitor and an inductor coupled in series between the RF transceiver node and ground. The inductor of the tunable notch filter may include a bondwire coupled between a semiconductor die and a semiconductor package. The inductance may include a physical inductor mounted on the package or a printed circuit board. The tunable notch filter may be enabled by a switch selectively coupling the filter to either the RF transceiver node or ground. The variable capacitor may be digitally programmed with digital values stored in a memory.

Frequency selective attenuator for optimized radio frequency coexistence

An antenna array that utilizes ground guard rings and metamaterial structures is disclosed. In certain embodiments, the antenna array is constructed from a plurality of antenna unit cells, wherein each antenna unit cell is identical. The antenna unit cell comprises a top surface, that contains a patch antenna and a ground guard ring. A reactive impedance surface (RIS) layer is disposed beneath the top surface and contains the metamaterial structures. The metamaterial structures are configured to present an inductance to the patch antennas, thereby allowing the patch antennas to be smaller than would otherwise be possible. In some embodiments, the metamaterial structures comprise hollow square frames. An antenna array constructed using this antenna unit cell has less coupling than conventional antenna arrays, which results in better performance. Furthermore, this new antenna array also requires less space than conventional antenna arrays.

Rotational symmetric AoX antenna array with metamaterial antennas

A phase-locked loop (PLL) that provides a local oscillator signal for a radio. An oscillator of the PLL supplies an oscillator output signal. Control logic receives a request to change the oscillator output signal to a new frequency and responds to the request by setting a first capacitor circuit of the oscillator to a first capacitance that corresponds to a predetermined frequency of the oscillator output signal. The control logic also responds to the request by setting one or more other capacitor circuits of the oscillator according to temperature and according to a frequency difference between the predetermined frequency and the new frequency. After responding to the request by setting the first capacitor circuit and the one or more other capacitor circuits, the PLL locks to the new frequency using a signal from the PLL loop filter to adjust another capacitor circuit in the oscillator.

Fast frequency synthesizer switching

A receiver concurrently demodulates data transmitted with a plurality of protocols. The receiver utilizes multiple and simultaneous protocol detections at preamble and/or packet payload phases. To provide robust detection and achieve fewer false detections, the receiver extends the cross correlation length once a short cross-correlation is valid. The receiver includes a first demodulator path and a second demodulator path with different filter bandwidths. The second demodulator path includes a decimator that reduces data by two. A correlator bank is coupled to the first and second demodulator paths and concurrently detects preamble symbols associated with a plurality of protocols. A first noise detector is coupled to the first demodulator path and a second noise detector is coupled to the second demodulator path. A first symbol identifier circuit is coupled to the first demodulator path and a second symbol identifier circuit coupled to the second demodulator path to provide packet payload symbol detection.

Context switching demodulator and symbol identifier

A system and method for one-way ranging is disclosed. The system comprises a transmitter, also referred to as tag, transmitting a packet having a first frequency. The receiver, also referred to as the locator, receives the first frequency and measures the phase at a specific point in time. At a predetermined time, the transmitter switches to a second frequency. This is performed while maintaining phase continuity. The receiver also switches to the second frequency at nearly the same time. The receiver then measures the phase of the second frequency at a second point in time. Based on these two phase measurements, the distance between the transmitter and the receiver may be calculated.

One way ranging synchronization and measurement

Metamaterial antenna array with isolated antennas

Growing community of inventors

Pflugerville, TX, United States of America

Terry Lee Dickey