Patent application number | Description | Published |
20090108949 | TEMPERATURE COMPENSATION FOR CRYSTAL OSCILLATORS - Methods and apparatus for generating a temperature compensated frequency estimate for a crystal oscillator, wherein the temperatures of the crystal and oscillator are both accounted for. A crystal temperature measurement is used to generate a first frequency component. The difference between the oscillator temperature measurement and a second temperature is scaled, and used to generate a second frequency component. The first and second frequency components may be summed to produce a frequency estimate for the crystal oscillator. In an embodiment, the computations may be performed in the slope domain. | 04-30-2009 |
20090195322 | CRYSTAL OSCILLATOR FREQUENCY CALIBRATION - Techniques are disclosed for estimating a frequency of a crystal oscillator based on temperature. In an embodiment, the oscillator frequency is computed using a polynomial approximation. Techniques are disclosed for deriving and periodically updating the coefficients used in the polynomial approximation. | 08-06-2009 |
20100002815 | DYNAMIC FILTERING FOR ADJACENT CHANNEL INTERFERENCE SUPPRESSION - A method for adjacent channel interference suppression comprises the steps of receiving a composite signal including a signal of interest and possibly one or more adjacent channel interferers, measuring the signal of interest and the possibly one or more adjacent channel interferers, and adjusting a location of at least one dynamic filter to extract the signal of interest. A receiver apparatus comprises an antenna configured to receive a composite signal including a signal of interest and possibly one or more adjacent channel interferers, an interference measurement circuit configured to measure the signal of interest and the possibly one or more adjacent channel interferers, at least one dynamic filter configured to extract the signal of interest, and a processor configured to adjust a location of at least one dynamic filter to extract the signal of interest. | 01-07-2010 |
20110095791 | LOW-POWER OSCILLATOR - Techniques for synthesizing a signal having a desired frequency from an oscillation signal. In an aspect, a reference signal having a known frequency may be periodically used to determine a ratio between the desired frequency and the frequency of the oscillation signal. The oscillation signal may be decimated by the ratio to generate a synthesized signal having approximately the desired frequency. In an aspect, the decimation may be performed by generating a pulse in response to the output of an accumulator that accumulates in steps of the ratio. To save power, the oscillation signal may be derived from a low-power oscillator, while the reference signal may be turned on only during periodic calibration. Further aspects for improving the frequency accuracy of the synthesized signal are disclosed. | 04-28-2011 |
20130307727 | DEVICES, METHODS, AND SYSTEMS FOR ANTENNA SWITCHING BASED ON LOOK-BACK - This disclosure provides systems, methods, and apparatus for antenna switching for simultaneous communication. An can include a plurality of antennas including a first antenna and a second antenna. The apparatus can further includes a plurality of receive circuits including a first receive circuit. The apparatus can further include a controller configured to determine one or more performance characteristics of the first antenna at a first time. The controller is further configured to determine a difference between the one or more performance characteristics of the first antenna at the first time and one or more performance characteristics of the first antenna at an earlier time. The controller is further configured to selectively switch the first receive circuit from receiving wireless communications via the first antenna to receive wireless communications via the second antenna if the difference is larger than a threshold. Other aspects, embodiments, and features are also claimed and described. | 11-21-2013 |
20130308476 | METHODS AND SYSTEMS FOR ANTENNA SWITCHING BASED ON UPLINK METRICS - This disclosure provides systems, methods, and apparatus for antenna switching for simultaneous communication. In one embodiment, a wireless communication apparatus is provided. The wireless communication apparatus includes a plurality of antennas including a first antenna and a second antenna. The wireless communication apparatus further includes a plurality of transmit circuits including a first transmit circuit. The wireless communication apparatus further includes a controller configured to selectively switch the first transmit circuit from transmitting wireless communications via the first antenna to transmit wireless communications via the second antenna based on one or more uplink performance characteristics of at least one of the first antenna and the second antenna. Other aspects, embodiments, and features are also claimed and described. | 11-21-2013 |
20150056933 | TX ANTENNA SELECTION FOR LTE IN MULTIPLE RADIO DEVICES - Device antennas may be allocated such that a non-LTE module (e.g., GSM module or 1x module) shares the same antenna with an LTE DRx module. This may lead to degradation of a non-LTE voice service when the LTE DRx module performs LTE transmit antenna selection causing the non-LTE module to be switched to a different antenna during reception/transmission of voice slots, resulting in a loss of slots. Accordingly, a method, an apparatus, and a computer program product for controlling antenna switching are provided. The apparatus facilitates a first radio module to use a first antenna for performing a first operation, detects that a second radio module will attempt to use the first antenna during transmit antenna selection for performing a second operation, and determines whether to switch use of the first antenna from the first radio module to the second radio module based on a type of the first operation. | 02-26-2015 |
Patent application number | Description | Published |
20100327986 | ENHANCING DEVICE RELIABILITY FOR VOLTAGE CONTROLLED OSCILLATOR (VCO) BUFFERS UNDER HIGH VOLTAGE SWING CONDITIONS - A circuit for a voltage controlled oscillator (VCO) buffer is described. The circuit includes a first capacitor connected to an input of the VCO buffer that is connected to a VCO core. The circuit also includes a second capacitor connected to the input of the VCO buffer and the gate of a p-type metal-oxide-semiconductor field effect (PMOS) transistor. The circuit further includes a first switch connected to the first capacitor and the gate of the PMOS transistor. The circuit also includes a third capacitor connected to the input of the VCO buffer. The circuit further includes a fourth capacitor connected to the input of the VCO buffer and the gate of an n-type metal-oxide-semiconductor field effect (NMOS) transistor. The circuit also includes a second switch connected to the third capacitor and the gate of the NMOS transistor. | 12-30-2010 |
20110051838 | DRIVING A MIXER WITH A DIFFERENTIAL LO SIGNAL HAVING AT LEAST THREE SIGNAL LEVELS - The mixer of a transmit chain of a wireless transmitter (such as the transmitter of a cellular telephone handset) is driven with low third harmonic in-phase (I) and quadrature (Q) signals. The low third harmonic I and Q signals have three or more signal levels, and transition between the these three or more signal levels at times such that each of the I and Q signals approximates a sine wave and has minimal third harmonic spectral components. In one example, reducing the third harmonic components of the I and Q signals simplifies design of amplifier stages of the transmitter and helps reduce receive band noise. | 03-03-2011 |
20110128084 | METHODS AND APPARATUS FOR INDUCTORS WITH INTEGRATED PASSIVE AND ACTIVE ELEMENTS - An integrated circuit is described. The integrated circuit includes an inductor that has a large empty area in the center of the inductor. The integrated circuit also includes additional circuitry. The additional circuitry is located within the large empty area in the center of the inductor. The additional circuitry may include a capacitor bank, transistors, electrostatic discharge (ESD) protection circuitry and other miscellaneous passive or active circuits. | 06-02-2011 |
20120013387 | WIDEBAND BALUN HAVING A SINGLE PRIMARY AND MULTIPLE SECONDARIES - An RF transmitter capable of transmitting over a wide range of frequencies includes a mixer, a wideband high-Q balun, a first driver amplifier and a second driver amplifier. The balun has a single primary winding and two secondary windings. A differential output of the mixer is coupled to the primary winding. A first of the two secondary windings is coupled to drive the first driver amplifier. A second of the two secondary windings is coupled to drive the second driver amplifier. One driver amplifier is used when transmitting at lower frequencies whereas the other driver amplifier is used when transmitting at higher frequencies. By appropriate sizing of the inductances of the secondary windings and by switching out one of the secondary windings at certain times, the balun is tunable to operate over the wide frequency range while having a high quality factor Q, thereby facilitating reduced power consumption while simultaneously meeting performance requirements. | 01-19-2012 |
20120025927 | RF ISOLATION SWITCH CIRCUIT - In a first aspect, an RF switch includes a main transistor and a gate-to-source shorting circuit. When the RF switch is turned off, the gate-to-source shorting circuit is turned on to short the source and gate of the main transistor together, thereby preventing a Vgs from developing that would cause the main transistor to leak. When the RF switch is turned on, the gate-to-source shorting circuit is turned off to decouple the source from the gate. The gate is supplied with a digital logic high voltage to turn on the main transistor. In a second aspect, an RF switch includes a main transistor that has a bulk terminal. When the RF switch is turned off, the bulk is connected to ground through a high resistance. When the RF switch is turned on, the source and bulk are shorted together thereby reducing the threshold voltage of the main transistor. | 02-02-2012 |
20120135698 | PROGRAMMABLE ATTENUATOR - Disclosed are circuits, techniques and methods for implementing an attenuator in a signal transmission path. In one particular implementation, an attenuation may be adjusted based, at least in part, on a control signal. In another implementation, such an attenuation may be adjusted in coarse increments by varying one or more gate voltages applied one or more transistors. In yet another implementation, adjusting said attenuation in fine increments by varying a bias voltage applied to at least one level shifter. | 05-31-2012 |
20130300489 | ADAPTABLE MIXER AND LOCAL OSCILLATOR DEVICES AND METHODS - An adaptable mixer device is operable in a first mode and a second mode and includes a first set of mixer units operable in the first mode and a second set of mixer units operable in the second mode. The second set of mixer units includes at least one mixer unit that is common to both the first set of mixer units and the second set of mixer units. The second set of mixer units also includes a plurality of mixer units that are not in the first set of mixer units. Similarly, the first set of mixer units including a plurality of mixer units that are not in the second set of mixer units. | 11-14-2013 |
Patent application number | Description | Published |
20090003427 | BURSTY INTERFERENCE SUPPRESSION FOR COMMUNICATIONS RECEIVERS - Techniques are provided for suppressing interference by taking into account the possible bursty nature of co-channel interference in a communication system. In an aspect, interference levels are separately computed for first and second data portions of a desired signal. The computed interference levels may be used to scale the corresponding data portions for subsequent processing. | 01-01-2009 |
20100046660 | INTERFERENCE CANCELLATION UNDER NON-STATIONARY CONDITIONS - A method for timing and frequency synchronization in a wireless system is provided. The method comprises the steps of receiving a burst of symbols, selecting a subset of the burst of symbols, iteratively adjusting the subset of the burst of symbols by a plurality of timing offsets and calculating, for each timing offset, a first performance metric corresponding to the adjusted subset. The method further comprises the steps of determining one of the plurality of timing offsets to be a preferred timing offset based upon the first performance metric thereof, iteratively rotating the subset of the burst of symbols by a plurality of frequency offsets and calculating, for each frequency offset, a second performance metric corresponding to the rotated subset, and determining one of the plurality of frequency offsets to be a preferred frequency offset based upon the second performance metric thereof. | 02-25-2010 |
20110305303 | INTERFERENCE CANCELLATION UNDER NON-STATIONARY CONDITIONS - A method for timing and frequency synchronization in a wireless system is provided. The method comprises the steps of receiving a burst of symbols, selecting a subset of the burst of symbols, iteratively adjusting the subset of the burst of symbols by a plurality of timing offsets and calculating, for each timing offset, a first performance metric corresponding to the adjusted subset. The method further comprises the steps of determining one of the plurality of timing offsets to be a preferred timing offset based upon the first performance metric thereof, iteratively rotating the subset of the burst of symbols by a plurality of frequency offsets and calculating, for each frequency offset, a second performance metric corresponding to the rotated subset, and determining one of the plurality of frequency offsets to be a preferred frequency offset based upon the second performance metric thereof. | 12-15-2011 |
20110312275 | SIGNAL RECEPTION METHOD AND APPARATUS FOR NON-STATIONARY CHANNELS - A signal reception method includes receiving a signal over a channel, producing a first equalized signal, a first interference suppression filter and a first estimate of the channel using a portion of a the received signal, dividing the received signal into a plurality of signal blocks, and for each one of the plurality of signal blocks, producing a second equalized signal using a portion of the first equalized signal by selecting from one of a linear estimator or a non-linear estimator and estimating symbols received in the one of the plurality of signal blocks based on the second equalized signal. | 12-22-2011 |
20140105126 | APPARATUS AND METHODS FOR ENHANCED MAXIMUM POWER IN MULTICARRIER WIRELESS COMMUNICATIONS - Aspects of the present disclosure are directed to improving maximum transmit power in multi-carrier reverse-link transmission. In one aspect, a method of carrier management for a multi-carrier reverse link transmission is disclosed. A method can include transmitting a reverse link signal on a plurality of carriers, and the reverse link signal including payload data and overhead data. A method can funnel payload data onto a first carrier of the plurality of carriers, while maintaining transmission of the overhead data on all the carriers of the plurality of carriers. Other aspects, embodiments, and features are also claimed and described. | 04-17-2014 |
20150063632 | SYSTEMS, DEVICES AND METHODS FOR TRACKING OBJECTS ON A DISPLAY - Systems, devices and methods for improved tracking with an electronic device are disclosed. The disclosures employ advanced exposure compensation and/or stabilization techniques. The tracking features may therefore be used in an electronic device to improve tracking performance under dramatically changing lighting conditions and/or when exposed to destabilizing influences, such as jitter. Historical data related to the lighting conditions and/or to the movement of a region of interest containing the tracked object are advantageously employed to improve the tracking system under such conditions. | 03-05-2015 |