Patent application number | Description | Published |
20080240024 | METHOD AND APPARATUS FOR DETECTING AND IDENTIFYING SPECTRUM OPPORTUNITIES | 10-02-2008 |
20090034508 | METHOD AND APPARATUS FOR SPECTRUM SHARING BETWEEN AN INCUMBENT COMMUNICATIONS SYSTEM AND A COGNITIVE RADIO SYSTEM - Efficient frequency spectrum sharing between at least one incumbent communication system(s) ( | 02-05-2009 |
20090054095 | SYSTEM AND METHOD FOR PERFORMING COMMUNICATION IN A WIRELESS COMMUNICATION NETWORK - A wireless communication network is provided in which a plurality of radio devices achieve frequency diversity. By utilizing cognitive capability within the radio devices to iteratively select frequency sets, a lowest cardinality frequency set is generated and used to communicate amongst the plurality of radio devices. Each radio device can have different hardware, as the iterative selection of frequency set can take into account the different hardware capabilities of the radio devices. | 02-26-2009 |
20090111463 | INCUMBENT SPECTRUM HOLD DEVICE - A monitoring device ( | 04-30-2009 |
20090135744 | OPPORTUNISTIC SPECTRUM SENSING OPTIMIZATION FOR A COMMUNICATION SYSTEM - A combination of subscriber clustering and link interleaving provides a cognitive radio system (CR) | 05-28-2009 |
20090298522 | COEXISTENCE AND INCUMBENT PROTECTION IN A COGNITIVE RADIO NETWORK | 12-03-2009 |
20090323835 | METHOD AND APPARATUS FOR DETECTION OF ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING (OFDM) SIGNALS BY COGNITIVE RADIOS - Efficient frequency spectrum sharing between at least one incumbent communication system(s) ( | 12-31-2009 |
20100069013 | METHOD AND APPARATUS FOR DISTRIBUTED SENSING MANAGEMENT AND CONTROL WITHIN A COGNITIVE RADIO NETWORK - A technique for spectrum sensing management and control for a secondary communication system seeking to utilize another communication system's spectrum is provided ( | 03-18-2010 |
20100081449 | METHOD AND APPARATUS FOR OPTIMIZING SPECTRUM UTILIZATION BY A COGNITIVE RADIO NETWORK - A technique for a secondary communication system to utilize spectrum designated to another (or primary) communication system is provided. By ranking a plurality of secondary base stations based on base station transmit power, calculated required transmit power and path loss, a set of criteria is developed for selecting a highest ranked secondary base station for operation within a primary's spectrum. The ranking may be adapted based on mobility of the secondary's subscriber; and as such the secondary system communicates within the primary's spectrum using the adaptively ranked base stations. Channel selection may also be ranked. The technique and apparatus allows a cognitive radio (CR) network to operate within an incumbent network's spectrum. | 04-01-2010 |
20100103924 | METHOD AND SYSTEM FOR WIRELESS MULTI-HOPPING COMMUNICATION | 04-29-2010 |
20100105345 | METHOD AND DEVICE FOR DETECTING PRESENCE OF A CARRIER SIGNAL IN A RECEIVED SIGNAL - A device receives a signal and, prior to demodulating the signal determines whether carrier is present in the received signal based on the correlation depth of the received signal. The device determines a plurality of values for the received signal that indicate the amount of correlation in the received signal and detects the presence of the carrier in the received signal as a function of the plurality of values. The plurality of values can include autocorrelation values and prediction coefficients, wherein the autocorrelation values are estimated based on an autocorrelation function derived for the received signal, and the prediction coefficients are generated using a prediction model that is derived as a function of the autocorrelation values. The prediction coefficients can be summed to generate a decision statistic that is compared to a detection threshold to detect the presence of the carrier. | 04-29-2010 |
20100137014 | METHOD TO IMPROVE DIVERSITY GAIN IN A COOPERATIVE SPECTRUM SENSING NETWORK - A cooperative sensing technique ( | 06-03-2010 |
20100144303 | METHOD AND APPARATUS FOR REMOVING DC OFFSET IN A DIRECT CONVERSION RECEIVER - A method and apparatus for correcting direct current (DC) offset errors of a received signal in a direct conversion receiver (DCR) are provided. DC offset correction algorithms are incorporated into the DCR, each algorithm being optimized for a particular receive signal operating environment. The DC offset correction algorithms remove DC offset errors in baseband In-phase and Quadrature-phase signals received within the direct conversion receiver baseband signal path. Individual DC offset correction algorithms are selected for use as determined by a signal quality estimator component. A DC offset correction component of the direct conversion receiver determines an appropriate DC offset correction algorithm suited for a particular operating environment. A criterion for a signal quality estimate is set to control transitioning between DCOC algorithms. A dual threshold strategy may be adopted to transition between one DC offset correction algorithm and another DC offset correction algorithm to provide hysteresis. | 06-10-2010 |
20100144357 | ALLOCATION OF CHANNELS IN A DEDICATED FREQUENCY SPECTRUM ON A SECONDARY BASIS - Allocation of channels in a dedicated frequency spectrum on a secondary basis. A direct mode communication request ( | 06-10-2010 |
20100222007 | NARROWBAND SYSTEM AND METHOD FOR DEFINING NARROWBAND CHANNELS IN UNUSED WIDEBAND CHANNELS - A narrowband communication system ( | 09-02-2010 |
20100248631 | DYNAMIC SPECTRUM ALLOCATION (DSA) IN A COMMUNICATION NETWORK - A method of dynamically allocating RF communication channels to a wireless communication device ( | 09-30-2010 |
20100303026 | METHOD AND APPARATUS FOR ZONE CONTROLLER BASED DYNAMIC SPECTRUM ALLOCATION - The application discloses a method and apparatus for dynamic spectrum allocation to a secondary communication system seeking to operate within the spectrum of a regulated primary communication system. The method includes clustering a plurality of secondary devices based on an operating frequency utilized by each of the secondary devices. The method then includes assigning sensing opportunities to the plurality of clustered secondary devices. The method then includes, receiving sensing information from each of the clustered secondary devices. The sensing information indicates at least one of an occupied channel frequency and an unoccupied channel frequency in the spectrum. The method further includes determining at least one spectrum opportunity, in the spectrum, that is unoccupied by each of a plurality of primary devices based on the received sensing information, and allocating the at least one spectrum opportunity to at least one of the secondary devices. | 12-02-2010 |
20100329180 | METHOD FOR OPTIMIZING SPATIAL DIVERSITY GAIN OF A SET OF NODES USED FOR COOPERATIVE SENSING - A group of nodes used for sensing in a cooperative sensing communication system ( | 12-30-2010 |
20110026643 | CARRIER DETECT SYSTEM, APPARATUS AND METHOD THEREOF - A method of detecting an on-channel signal and synchronizing signal detection with correcting for DC offset errors in a direct conversion receiver is presented. A received signal is digitized, and a state machine operates to detect the presence of an on-channel signal. If the signal is not detected, a mixed mode training sequence is initiated in which the DC offset errors in both an analog and digital received signal path are corrected. While training, processing of the digitized samples by a digital signal processor and a host controller is suspended (while they are put into battery save mode) and the gain provided to subsequently received signals is minimized. The DC offset correction circuitry is bypassed and put into battery save mode at predetermined periods when DC offset correction is not performed. | 02-03-2011 |
20110105036 | METHOD AND APPARATUS FOR SENSING PRESENCE OF AN INCUMBENT SIGNAL ON A SECONDARY RADIO CHANNEL - A remote station communicates with a base station over a secondary radio channel. During communication, the remote station determines channel conditions of the secondary radio channel. Based on the channel conditions, the remote station selects one or more sensing methods to be performed on the secondary radio channel. The result of performing the sensing method is used to determining whether an incumbent signal is present on the secondary radio channel. | 05-05-2011 |
20110312294 | AUDIO HOLE SUPPRESSION METHOD AND APPARATUS FOR A TWO-WAY RADIO - A channel scanning technique and apparatus provides audio hole suppression in two-way radio communications. Upon detecting the absence of a carrier signal on a priority channel during a priority scan mode of operation, a training waveform is constructed upon returning to the home-channel. The training waveform is applied to audio shaping filters within an audio lineup to suppress transients and minimize or eliminate the occurrence of audio pops at a speaker output thereby reducing the audio hole. | 12-22-2011 |
20120064853 | SYSTEM AND METHOD FOR MANAGING POWER CONSUMPTION IN A DEVICE - Systems and methods for managing power consumption in a device include toggling an ON-OFF setting of apparatus, which controls a carrier detector. The toggling is carried out according to a first duty cycle having a fixed OFF-time duration and a first dwell time having a first dwell time duration during which the carrier detector performs radio frequency carrier detection function. The device receives at least one input that affects the radio frequency carrier detection function, and the first duty cycle is changed to a second duty cycle. The toggling is carried out according to the second duty cycle, which has the same fixed OFF-time duration of the first duty cycle and a second dwell time having a second dwell time duration that is longer than the first dwell time duration, during which the radio frequency carrier detection function is performed. | 03-15-2012 |
20120129480 | APPARATUS FOR RECEIVING MULTIPLE INDEPENDENT RF SIGNALS SIMULTANEOUSLY AND METHOD THEREOF - An apparatus and method for receiving and processing multiple independent, uncorrelated RF signals is presented. The apparatus includes a Hybrid-Direct Conversion Receiver incorporating front end branches, protocol-specific digital processing branches, an interference detector, a correlator, and an offset control for controlling oscillator sources. The front end branches each contain a preselector that filters received signals and a mixer that down converts the received signal to an IF offset from a reference frequency by a unique offset. The bandwidth of an IF processor is partitioned into sub-channels corresponding to the different offsets and is wider than the combination of the sub-channels. The interference detector and correlator determine whether a particular desired signal is degraded by interference signals and select a new sub-channel. This information is provided to the offset control, which adjusts a LO source coupled to the corresponding down mixer accordingly. | 05-24-2012 |
20120171975 | METHOD FOR CONTROLLING PEAK-TO-AVERAGE POWER RATIO OF SINGLE CARRIER FDMA SYSTEM - A method for controlling peak-to-average power ratio prior to amplification by a power amplifier is provided. The peak sample of a signal is predicted, window length is adjusted based on the peak width around the peak sample or subcarriers used to transmit the signal, and the window is subsequently used to clip the samples. A peak suppression window may be applied prior to predicting the peak sample when a set number of samples exceed a predetermined threshold. Window clipping may be deactivated if interference and throughput of the power amplifier is detrimentally affected. A pulse shaping filter may be optimized based on the window clipping to control transmitted signal characteristics. Various thresholds used in the prediction may be initially based on system design and power amplifier linearity and then dynamically adjusted based on an estimation of active subcarriers or of interferers present in the communication system. | 07-05-2012 |
20120238309 | METHOD AND APPARATUS FOR OPTIMIZING SPECTRUM UTILIZATION BY A COGNITIVE RADIO NETWORK - A technique for a secondary communication system to utilize spectrum designated to another (or primary) communication system is provided. By ranking a plurality of secondary base stations based on base station transmit power, calculated required transmit power and path loss, a set of criteria is developed for selecting a highest ranked secondary base station for operation within a primary's spectrum. The ranking may be adapted based on mobility of the secondary's subscriber; and as such the secondary system communicates within the primary's spectrum using the adaptively ranked base stations. Channel selection may also be ranked. The technique and apparatus allows a cognitive radio (CR) network to operate within an incumbent network's spectrum. | 09-20-2012 |
20130148761 | METHOD FOR CORRECTING IMBALANCE ERRORS IN A DIRECT CONVERSION RECEIVER - A communication system comprises a direct conversion receiver for correcting imbalance errors. The direct conversion receiver receives a radio frequency (RF) signal and converts the RF signal to baseband signals. The direct conversion receiver further translates the baseband signals to digital signals having a direct current (DC) offset and applies a DC offset correction to the digital signals having the DC offset to generate first DC offset corrected signals. An imbalance correction unit of the direct conversion receiver applies an imbalance correction to the first DC offset corrected signals by estimating an error between an average envelope of the first DC offset corrected signals and an average envelope of second DC offset corrected signals. The imbalance correction unit is fixed at initial imbalance parameter values. The direct conversion receiver further updates the initial imbalance parameter values of the imbalance correction unit based on the estimated error for correcting imbalance errors. | 06-13-2013 |
20140220919 | AUTOMATIC FREQUENCY CONTROL METHODS AND APPARATUS - Embodiments include Direct-Conversion Receiver (DCR) apparatus, and methods for performing automatic frequency control based on a received signal. An initial frequency offset value is selected from a lookup table and applied to the receiver's local oscillator. Digital samples are generated based on the received signal, and stored in a buffer in sequential order. A DC estimator performs multiple iterations of a DC component estimation process. The process includes iteratively applying an analysis window to more recently-stored, buffered samples, in order to identify a set of the buffered samples. Within the set of buffered samples, an intermediate value between the amplitudes of two samples is determined (e.g., samples having the largest and smallest amplitudes). Between at least some of the multiple iterations, the number of samples that defines the size of the analysis window is increased. | 08-07-2014 |
20140269851 | SYSTEMS, METHODS, AND DEVICES FOR IMPROVING SIGNAL DETECTION IN COMMUNICATION SYSTEMS - Systems, devices, and methods to improve signal detection of a receiver in communication systems, including receiving a signal having one or more distorted versions of a predetermined waveform as well as processing the received signal with a plurality of eigenfilters generated from eigenvectors of a covariance matrix of the predetermined waveform. Further a correlation output is generated by further processing the received signal with at least one matched filter formed from an eigenfiltered version of the predetermined waveform and identifying at least one peak in the correlator output. The peak may be used to improve performance of the receiver. | 09-18-2014 |
20150017941 | METHOD AND APPARATUS FOR USING ERASURE TO IMPROVE SIGNAL DECODING DURING AN INTERFERENCE EVENT - A method and apparatus for using erasure to improve signal decoding when data is impacted by an interference event. Embodiments may include receiving in an RF receiver a desired on-channel signal that includes an information signal modulated on to the desired on-channel signal; generating a sampled received signal with an analog-to-digital (A/D) converter; detecting an interference event using an interference detector as well as generating a mask based on the interference event; processing the sampled received signal using the mask to generate decoding data for use by a soft decoder; and, providing the decoding data to the soft decoder. | 01-15-2015 |