ATHEROS COMMUNICATIONS, INC. Patent applications |
Patent application number | Title | Published |
20150071335 | SYSTEMS AND METHODS FOR COMPENSATING ANTENNA GAIN IMBALANCE - This disclosure involves methods and systems for compensating for imbalanced transmit antenna gains. A transmit controller independently samples the received signal in each chain of a transceiver selectively adjusts the transmit power at each antenna to minimize any indicated imbalance to improve performance at the node receiving the transmission. | 03-12-2015 |
20120300812 | PAGING CHANNEL PREDICTION FOR BLUETOOTH PAGING PROCEDURE - A Bluetooth paging procedure can implement a mechanism for predicting a Bluetooth paging channel in a paging channel hopping sequence. One or more Bluetooth paging channels, on which one or more page requests intended for a Bluetooth device were received, are determined from a plurality of Bluetooth communication channels. One of a plurality of paging channel hopping sequences associated with the Bluetooth device that comprises each of the one or more determined Bluetooth paging channels is identified. A time delay associated with determining a target Bluetooth paging channel from the plurality of Bluetooth communication channels on which to transmit a page response is determined. The target Bluetooth paging channel is determined based, at least in part, on the identified one of the plurality of the paging channel hopping sequences and the time delay. | 11-29-2012 |
20120281638 | CONCURRENT BACKGROUND SPECTRAL SCANNING FOR BLUETOOTH PACKETS WHILE RECEIVING WLAN PACKETS - A Bluetooth detection unit can be implemented to minimize the time required for executing the inquiry and paging scan procedures on a Bluetooth device associated with a collocated WLAN device. The Bluetooth detection unit can execute concurrent background spectral scanning to detect Bluetooth control packets while the WLAN device is receiving WLAN packets. The Bluetooth detection unit can analyze, for each Bluetooth control channel, the Bluetooth device can determine energy measurements associated with each Bluetooth control channel and can determine whether each Bluetooth control channel comprises a narrowband signal based, at least in part, on frequency domain samples associated with an RF signal received at the WLAN device. The Bluetooth detection unit can determine which of the Bluetooth control channels comprise a Bluetooth control packet. | 11-08-2012 |
20120271902 | SELECTING FORWARDING DEVICES IN A WIRELESS COMMUNICATION NETWORK - A forwarding device can establish a communication link with both a source device and a destination device to extend the communication range of the source device by forwarding data from the source device to the destination device. A coordinating device can be configured to identify a forwarding client through which to communicate with a client station that is inaccessible to the coordinating device via a direct communication link, based on the throughput achieved on communication links between the coordinating device, the inaccessible client, and accessible clients. The throughput achieved on the communication links can be determined by exchanging training packets, receiving acknowledgement messages in response to the training packets, and subsequently analyzing the received acknowledgement messages. Based on the calculated throughputs, one of the accessible clients can be designated as the forwarding client with respect to the coordinating device and the inaccessible client. | 10-25-2012 |
20120236716 | PROFILE-BASED QUALITY OF SERVICE FOR WIRELESS COMMUNICATION SYSTEMS - A profile-based quality of service (QoS) priority assignment mechanism can be implemented in a wireless communication network. In one embodiment, a plurality of network identifiers (e.g., SSIDs) associated with a plurality of client network devices that are communicatively coupled with an access point of the wireless communication network are determined. It is further determined which QoS profile of a plurality of QoS profiles supported by the access point is associated with each network identifier associated with each of the plurality of client network devices. A plurality of pending communications associated with the plurality of network devices are detected. A QoS transmission priority level is assigned to each of the pending communications associated with the plurality of network devices based, at least in part, on the QoS profile associated with each pending communication. A transmission of data associated with one of the plurality of pending communications is initiated based, at least in part, on the QoS transmission priority level assigned to each pending communication. | 09-20-2012 |
20120230221 | SYSTEMS AND METHODS FOR IMPLEMENTING AD HOC WIRELESS NETWORKING - This disclosure involves methods and systems for implementing IBSS networks between peer client devices. Devices function as registrar or enrollee in the network depending upon whether they are in configured or unconfigured mode. The WPS-PBC configuration routine allows the unconfigured enrollee device to obtain the necessary network configuration profile from the configured registrar device upon a successful WPS handshake process. Once a device has received the network configuration protocol, its status is switched to configured, allowing it to function as a registrar for the network for the subsequent addition of new devices. When both devices are initially in an unconfigured state, one is chosen to act as registrar so that it can automatically generate the necessary network configuration profile and pass it along to the other device. Following this process, both devices are set to configured mode. | 09-13-2012 |
20120230206 | PLACEMENT OF WIRELESS REPEATERS IN A WIRELESS COMMUNICATION NETWORK - The position of wireless repeaters within a wireless communication network can affect the throughput and performance of the wireless communication network. A wireless repeater and/or an access point associated with the wireless communication network can be configured to determine the optimal position of the wireless repeater based on throughput achieved on communication links between the access point, the repeater, and/or the client stations. The throughput achieved on communication links between the access point, the repeater, and/or the client stations can be determined by exchanging training packets, receiving acknowledgement messages in response to the training packets, and subsequently analyzing the received acknowledgement messages. Furthermore, the throughput achieved on communication links between the access point, the repeater, and/or the client stations can also be analyzed to determine whether each of the client stations should associate with the access point or the wireless repeater. | 09-13-2012 |
20120207139 | MULTI-COMMUNICATION MODE PACKET ROUTING MECHANISM FOR WIRELESS COMMUNICATION SYSTEMS - The transmission range of a network communication device can be extended by enabling transition between legacy and non-legacy communication protocols. A communication device can receive a packet in a legacy packet format from a host device via a legacy network interface. In response to determining that the packet received via the legacy network interface is to be transmitted using one of a plurality of non-legacy communication protocols, a processing path within the communication device in accordance with which to process the packet for transmission using the non-legacy communication protocol is determined. The packet in the legacy packet format is reformatted to yield a target packet in a non-legacy packet format based, at least in part, on the non-legacy communication protocol. The target packet is provided to the destination network device in accordance with the non-legacy communication protocol. | 08-16-2012 |
20120188938 | SYSTEM AND METHOD FOR PROVIDING A LOCATION AWARE WIRELESS NETWORK - This disclosure is directed to devices and methods for providing a location aware wireless network including at least one network node that is configured to calculate a position estimate on the basis of signals received from other network nodes and to transmit location information based on the position estimate to other nodes on the network. Preferably, the network node is configured to autonomously determine a signal-derived position estimate, including those based on location information from other network nodes, signal strength or the timing of signals. Other network nodes can feature GPS receivers, which can optionally be configured to perform signal-derived estimates as well. | 07-26-2012 |
20120177161 | CALIBRATION OF SYNTHESIZER PHASE USING REFERENCE HARMONIC - Arbitrary phase variations of a shared frequency synthesizer can be calibrated using a reference harmonic each time the shared frequency synthesizer is allocated to a network device to enable one frequency synthesizer to be shared between multiple network devices. On determining that the shared frequency synthesizer has been allocated to the network device, an output frequency of the shared frequency synthesizer can be aligned with a predetermined reference frequency that is associated with an operating frequency band of the network device. A phase correction factor associated with the shared frequency synthesizer can be calculated from a signal calculated based, at least in part, on the output frequency of the shared frequency synthesizer and the predetermined reference frequency. The phase correction factor is applied to a signal received at the network device to correct a phase error associated with the shared frequency synthesizer. | 07-12-2012 |
20120177027 | SYSTEM AND METHOD FOR TIME SYNCHRONIZING WIRELESS NETWORK ACCESS POINTS - This disclosure is directed to devices and methods for providing a time synchronized WLAN system. Stationary APs in a WLAN system can determine accurate timing information from a GNSS satellite, so as to synchronize with each other. The synchronized APs can then be used to determine position information for devices on the network using pseudo-ranging techniques. | 07-12-2012 |
20120170557 | COEXISTENCE MECHANISM FOR COLLOCATED WLAN AND WWAN COMMUNICATION DEVICES - Wireless radio devices that communicate in close proximity to each other typically suffer from interference. Such interference between collocated wireless radio devices can lead to degradation in performance of one or both of the wireless radio devices. Functionality can be implemented to coordinate communications of collocated WLAN and WWAN devices to minimize interference between the WLAN device and the WWAN device. The WWAN device can determine a WWAN communication time interval associated with the WWAN device for performing WWAN communication operations and a WLAN communication time interval associated with the WLAN device for performing WLAN communication operations. In response to determining that the WWAN communication time interval is in progress, WWAN communication operations can be performed at the WWAN device. In response to determining that the WWAN communication time interval is not in progress, the WWAN device can delay performing the WWAN communication operations. | 07-05-2012 |
20120170556 | COEXISTENCE MECHANISM FOR COLLOCATED WLAN AND WWAN COMMUNICATION DEVICES - Wireless radio devices that communicate in close proximity to each other typically suffer from interference. Such interference between collocated wireless radio devices can lead to degradation in performance of one or both of the wireless radio devices. Functionality can be implemented to coordinate communications of collocated WLAN and WWAN devices to minimize interference between the WLAN device and the WWAN device. The WLAN device can determine a WLAN communication time interval associated with the WLAN device for performing WLAN communication operations and a WWAN communication time interval associated with the WWAN device for performing WWAN communication operations. In response to determining that the WLAN communication time interval is in progress, WLAN communication operations can be performed at the WLAN device. In response to determining that the WLAN communication time interval is not in progress, the WLAN device can delay performing the WLAN communication operations. | 07-05-2012 |
20120151089 | DIRECT DATA COMMUNICATION IN A PEER-TO-PEER NETWORK - A direct data communication link can be established for direct data communication between a first network device and a second network device of a peer-to-peer network. On determining to communicate with the second network device, the first network device can determine, based on a beacon message broadcast by a managing network device of the peer-to-peer network, whether the second network device supports a direct data communication protocol. If it is determined that both the first network device and the second network device support the direct data communication protocol, a set of handshake messages associated with the direct data communication protocol can be exchanged to establish the direct data communication link between the first network device and the second network device. Subsequent data messages can be exchanged between the first network device and the second network device via the direct data communication link. | 06-14-2012 |
20120140804 | OPTIMIZING DATA RATE OF MULTI-BAND MULTI-CARRIER COMMUNICATION SYSTEMS - Wired and wireless communication networks can be subject to noise and interference resulting data corruption. In a communication system comprising a first network device and a second network device, the first and the second network devices can be configured for optimizing the data rate of the communication system. On receiving a multi-band signal at the first network device from the second network device during a channel adaptation mode, the multi-band signal can be split into a plurality of independent frequency band signals. A performance measurement of a first of the plurality of frequency band signals corresponding to a lowest frequency band signal can be calculated. Communication parameters can be determined for each of the plurality of frequency band signals based on the performance measurement of the first of the plurality of frequency band signals. The communication parameters can be provided from the first network device to the second network device. | 06-07-2012 |
20120105280 | SYNCHRONIZED MEASUREMENT SAMPLING IN A NAVIGATION DEVICE - In a hot start mode of a navigation device, the process of obtaining pseudo-range measurements can be synchronized with the processes of tracking navigation satellites and initializing a positioning unit to compute a position, velocity, and time (PVT) solution of the navigation device. This can influence a time instant at which the pseudo-range measurements are determined and a time to first fix, depending on whether the navigation device is in a strong or weak signal environment. A measurement unit can receive a first indication that a predetermined number of navigation satellites have been acquired and that navigation signals transmitted by the acquired navigation satellites have been locked. The measurement unit can receive a second indication that the positioning unit has been initialized to compute the PVT solution. In response to receiving both indications, the measurement unit can obtain the pseudo-range measurements. Accordingly, the positioning unit can compute the PVT solution. | 05-03-2012 |
20120093240 | INTERFERENCE DETECTION IN A POWERLINE COMMUNICATION NETWORK - A powerline communication (PLC) network can be subject to noise/interference resulting in loss of throughput and data corruption for PLC devices connected to the PLC network. A powerline interference analyzer can be implemented in the PLC network for detecting sources of the noise. The powerline interference analyzer can determine powerline network noise characteristics that are representative of noise on the PLC network and can analyze the powerline network noise characteristics to determine one or more noise patterns. The noise patterns can be compared with a plurality of predefined noise signatures that are representative of corresponding each of a plurality of noise sources. Consequently, at least one noise source that is associated with the noise patterns can be identified from the plurality of the noise sources. | 04-19-2012 |
20120093151 | COEXISTENCE MECHANISM FOR NON-COMPATIBLE POWERLINE COMMUNICATION DEVICES - A powerline network may comprise powerline communication (PLC) devices of a first class of PLC devices that are incompatible with PLC devices of a second class of PLC devices. This can result in interference between communications of the first and the second classes of PLC devices. A dual mode PLC device that is compatible with the first and the second classes of PLC devices can be implemented for coexistence with both classes of PLC devices. The dual mode PLC device can determine whether the powerline network comprises a combination of PLC devices of the first and the second classes of PLC devices. One of a plurality of packet headers that is compatible with both the classes of PLC devices can be selected for transmission in response to determining that the powerline network comprises a combination of PLC devices of the first and the second classes of PLC devices. | 04-19-2012 |
20120072110 | INDOOR POSITIONING USING PRESSURE SENSORS - A pressure sensor can be implemented on a network device to minimize vertical positioning errors of the network device in an indoor environment. A reference altitude and a reference pressure associated with an access point in the indoor environment are received at the network device via a communication network. A pressure is determined at the network device in the indoor environment. An altitude of the network device associated with the pressure at the network device in the indoor environment is calculated based, at least in part, on the pressure at the network device, the reference pressure, and the reference altitude. A position of the network device in the indoor environment is determined based, at least in part, on the altitude of the navigation device and location information received from at least the access point. | 03-22-2012 |
20120063335 | PACKET IDENTIFICATION FOR POWER SAVING IN WIRELESS COMMUNICATION NETWORKS - A network coordinator can assign an association identifier (AID) and/or a group identifier (GID) to identify a client station to which a packet is to be transmitted and to enable the client station to determine whether to receive an incoming packet. The network coordinator can randomly generate a base AID that is representative of the network coordinator and can assign at least one AID to client stations to minimize the probability of client stations associated with proximate network coordinators being assigned the same AIDs. The network coordinator can also randomly assign at least one GID to a group of client stations to minimize the probability of groups of client stations associated with the proximate network coordinators being assigned the same GID. The client station can analyze indications of a received AID and/or received GID to determine whether to receive the packet or whether to switch to an inactive power state. | 03-15-2012 |
20120062421 | PHASE ROTATION TECHNIQUES IN A MULTI-USER WIRELESS COMMUNICATION ENVIRONMENT - A mechanism for mitigating inter-user interference in a multi-user wireless communication environment is disclosed. A first network device determines a plurality of steering matrices, associated with a corresponding plurality of subcarriers, for each of multiple destination devices associated with the first network device. A phase difference between corresponding steering vectors of each pair of consecutive steering matrices of the plurality of steering matrices associated with each of the destination devices is determined and phase rotation is performed to maintain phase continuity between the consecutive steering matrices. One or more pre-coding matrices are calculated based on at least a subset of the plurality of steering matrices associated with the multiple destination devices. The one or more pre-coding matrices are applied to data to be transmitted to the multiple destination devices to mitigate interference between each of the multiple destination devices. | 03-15-2012 |
20120059578 | POSITIONING NETWORK AVAILABILITY AND RELIABILITY BASED ROUTING - A routing system can be configured to determine a route based on availability and reliability of location reference devices to determine a most reliable route between a source and a destination. Visibility information that is indicative of availability of at least a threshold number of location reference devices along the route can be determined. For each of a plurality of routes between the source and the destination, a reliability rating associated with the route can be determined based on the visibility information associated with the route. The reliability rating is indicative of a reliability of the route and an ability of the routing system to maintain continuous connectivity to the at least the threshold number of location reference devices along the route. The reliability ratings of the plurality of routes are compared to identify and to present one of the plurality of routes with a highest reliability rating. | 03-08-2012 |
20120033682 | BALANCED BIT LOADING FOR COMMUNICATION NETWORKS SUBJECT TO BURST INTERFERENCE - Wired and wireless communication networks can be subject to burst interference resulting in loss of throughput and data corruption. In a communication system comprising a transmitting network device and a receiving network device, the transmitting network device can be configured to implement balanced bit loading for retransmitting packets of a failed packet transmission. On receiving a request for retransmission from the receiving network device, the transmitting network device can identify and eliminate sub-carriers that are associated with a bit load that is less than a predefined bit load threshold. The transmitting network device can attempt to reallocate bit loads of the eliminated sub-carriers to remaining sub-carriers across two or more constituent symbols per original symbol. | 02-09-2012 |
20120033619 | DYNAMIC BIT ALLOCATION FOR COMMUNICATION NETWORKS SUBJECT TO BURST INTERFERENCE - Wired and wireless communication networks can be subject to burst interference resulting in loss of throughput and data corruption. In a communication system comprising a transmitting network device and a receiving network device, the transmitting network device can be configured to implement a dynamic bit allocation technique for retransmitting packets of a failed packet transmission. On receiving a request for retransmission from the receiving network device, the transmitting network device can dynamically allocate bits of original symbols across two or more constituent symbols per original symbol. The transmitting network device can allocate the two or more constituent symbols across one or more retransmission packets to exploit time diversity. The transmitting network device can also vary modulation and coding schemes and other transmit parameters to generate robust retransmission packets. | 02-09-2012 |
20120014415 | TRANSMITTER BEAMFORMING STEERING MATRIX PROCESSING AND STORAGE - A mechanism for processing beamforming steering matrices in a transceiver system. A plurality of beamforming steering matrices associated with a plurality of subcarriers of an RF signal received at the transceiver system are generated. The beamforming steering matrices are compressed and stored. The beamforming steering matrices may also be grouped or sub-sampled prior to being stored. The beamforming steering matrices are decompressed and ungrouped before being applied to data to be transmitted. Prior to ungrouping the beamforming steering matrices, a phase difference between corresponding beamforming steering vectors of consecutive beamforming steering matrices is determined. Phase rotation is performed on the corresponding beamforming steering vectors based on the determined phase difference associated with the corresponding beamforming steering vectors to improve phase continuity between consecutive beamforming steering matrices. | 01-19-2012 |
20110268051 | SYSTEM AND METHOD FOR CONTROLLING WLAN AND BLUETOOTH COMMUNICATIONS - This disclosure involves methods and systems for controlling WLAN and Bluetooth communications by allocating bandwidth into times blocs having a first segment with Bluetooth priority and a second segment with WLAN priority. Access to the wireless communication medium is signaled over an interface connecting the WLAN and Bluetooth modules. Downlink traffic is modulated by signaling the WLAN access point to buffer traffic during the first segment. WLAN traffic can also be modulated by allowing reception and blocking transmission WLAN signals during the first segment. Further, while high priority Bluetooth transmission are preferably always allowed, low priority Bluetooth transmission can be restricted during the second period, depending upon the respective states of the WLAN and Bluetooth modules. A coexistence agent can be used to transfer relevant information between the WLAN and Bluetooth modules. | 11-03-2011 |
20110268024 | DETECTION OF CO-LOCATED INTERFERENCE IN A MULTI-RADIO COEXISTENCE ENVIRONMENT - Unscheduled transmissions of one wireless network device while a collocated wireless network device has control of a communication medium can corrupt packets received by the collocated wireless network device. Interference between the collocated wireless network devices can lead to degradation in performance of either/both the wireless network devices. In a communication system comprising a first wireless network device collocated with a second wireless network device, the first wireless network device can be configured to transmit a coexistence message to the second wireless network device when the first wireless network device transmits a packet without control of the communication medium. On receiving the coexistence message indicating that the first wireless network device transmitted a packet without control of the communication medium, the second wireless network device can discard any packets received at the second wireless network device and can request retransmission of the discarded packets. | 11-03-2011 |
20110057837 | SINGLE LOCAL OSCILLATOR FREQUENCY BAND TO RECEIVE DUAL-BAND SIGNALS - A dual-band GPS receiver and method and apparatus for downconversion of dual-band GPS signals. A dual-band GPS receiver in accordance with the present invention comprises an antenna, a Radio Frequency (RF) section, coupled to the antenna, and a baseband section, coupled to the RF section, wherein the RF section comprises a receiver, the receiver receiving signals from a first GPS frequency band and a second GPS frequency band, a local oscillator having a local oscillator frequency, and a mixer, coupled to the receiver and the local oscillator, for selectively mixing the local oscillator frequency with the first GPS frequency band and a second GPS frequency band, wherein the local oscillator frequency downconverts the first GPS frequency band and the second GPS frequency band into a common downconversion frequency band. | 03-10-2011 |
20100284316 | DYNAMIC ENERGY SAVING MECHANISM FOR ACCESS POINTS - Mobile access points typically run on batteries, and therefore, can operate for a limited amount of time without an external power source. However, because the access point service model requiring the access point to always be available and the access point's limited battery capacity reduces the time that the mobile access point can be used. Functionality can be incorporated in mobile access points to implement power saving mechanisms by altering the service model that requires the access point to always be available. Configuring the access point to enter into a low powered state for a predefined period of time can conserve mobile access point power and prolong battery life. Functionality for implementing power saving mechanisms can also be incorporated on fixed access points for efficient utilization of computing resources. | 11-11-2010 |
20100111212 | Decision Feedback Channel Estimation And Pilot Tracking for OFDM Systems - Current OFDM systems use a limited number of symbols and/or sub-channels to provide approximations for channel estimations and pilot tracking, i.e. phase estimations. For example, two training symbols in the preamble of a data packet are used to provide channel estimation. Four of the fifty-four sub-channels are reserved for providing phase estimation. However, noise and other imperfections can cause errors in both of these estimations, thereby degrading system performance. Advantageously, decision feedback mechanisms can be provided to significantly improve channel estimation and pilot tracking in OFDM systems. The decision feedback mechanisms can use data symbols in the data packet to improve channel estimation as well as data sub-channels to improve pilot tracking. | 05-06-2010 |
20090323524 | INVOKING DIFFERENT WIRELESS LINK RATE SELECTION OPERATIONS FOR DIFFERENT TRAFFIC CLASSES - Functionality can be implemented within a device or chip to select different sets of wireless link rate determination operations that account for different degrees of presentation time sensitivity that correspond to different classes of traffic. The device or chip can infer or explicitly determine presentation time sensitivity based, at least in part, on traffic class. The selected wireless link rate operations select link rates for the different classes of traffic. A first set of the wireless link rate determination operations can choose a smoother and more stable wireless link rate for the wireless traffic class that conveys presentation time sensitive content. A second of the wireless link rate determination operations can choose a fastest possible wireless link rate, which may be more susceptible to jitter and delay, for a traffic class that is less sensitive. | 12-31-2009 |
20090311979 | POLAR MODULATOR WITH PATH DELAY COMPENSATION - A modulation system comprising a signal processing unit and a modulator. The signal processing unit may generate a low frequency modulator signal, a high frequency modulator signal, and a modulator amplitude control signal. The modulator may generate a modulated signal for transmission via a wireless network based, at least in part, on the low frequency modulator signal, the high frequency modulator signal, and the modulator amplitude control signal. The signal processing unit comprises a delay compensation unit for delaying the generation of the high frequency modulator signal and the modulator amplitude control signal based, at least in part, on signal generation and modulation path delays associated with the low frequency modulator signal to substantially align the modulator signals at the output of the modulation system. | 12-17-2009 |
20090311972 | SYNTHESIZER AND MODULATOR FOR A WIRELESS TRANSCEIVER - A transceiver including a transmit modulator and a receiver. The modulator may accept a channel selection input, a first modulation input, a second modulation input, and an amplitude input. During transmit time slots, the modulator may generate a modulated output having a carrier frequency selected by the channel selection input. The carrier frequency may be frequency modulated by the first modulation inputs, phase modulated by the second modulation input, and amplitude modulated by the amplitude input. During receive time slots, the modulator may generate a carrier frequency selected by the channel selection input and offset by the first modulation input. The modulator may alternate between providing modulated transmit signals during transmit time slots and providing a local oscillator for the receiver during receive time slots. | 12-17-2009 |
20090285279 | PHASE FREQUENCY DETECTOR WITH PULSE WIDTH CONTROL CIRCUITRY - A phase frequency detector comprising a detection circuit and a reset circuit. The phase frequency detector may receive a feedback signal having a predetermined pulse width. The detection circuit may generate a first control signal based on a reference signal, and a second control signal based on the feedback signal. The reset circuit may generate a reset signal used for resetting the detection circuit based on the first control signal, the second control signal, and the feedback signal. The feedback signal may be tied to the generation of the reset signal such that, during a locked state, the pulse width of the second control signal is approximately equal to the pulse width of the feedback signal, which helps reduce the sensitivity of the circuit to nonlinearities. | 11-19-2009 |
20090072910 | VOLTAGE-CONTROLLED OSCILLATOR WITH CONTROL RANGE LIMITER - A voltage-controlled oscillator (VCO) comprising a first circuit, a second circuit, a comparator circuit, and a control unit. The first circuit can determine an output common mode voltage associated with an output of the VCO. The second circuit can generate an upper control voltage limit and a lower control voltage limit associated with a control voltage received by the VCO based, at least in part, on the output common mode voltage. The comparator circuit can compare the control voltage to the upper and lower control voltage limits. The control unit can determine whether to change a switched capacitance associated with the VCO based, at least in part, on whether the control voltage is outside the upper and lower control voltage limits, thereby maintaining an optimal region of operation for the control voltage. | 03-19-2009 |
20080248759 | Apparatus For Coupling A Wireless Communication Device To A Physical Device - A wireless communication device may be configured to transmit and receive data through a physical device, such as a cable. Relatively higher transmit radio frequency (RF) signals from the wireless communication device may be shifted to a relatively lower frequency, thereby enabling the relatively lower frequency signals to be carried by the physical device. Similarly, relatively lower frequency signals from the physical device may be shifted to relatively higher frequencies, thereby enabling the wireless communication device to receive the signals from the physical device. In one embodiment, the frequency of the RF signals may be between 2.3 and 2.7 GHz and the frequency of the relatively lower frequency shifted signals may be between 900 and 1100 MHz. | 10-09-2008 |