Abstract: A method for detecting a presence of an RF signal begins by forming with at least one computer processor a sample correlation matrix A from a sample of a radio frequency channel. Thereafter, the at least one computer processor determines a trace tr(A) of the sample correlation matrix and a determinant det(A) of the sample correlation matrix. The at least one processor then selectively determines a presence or absence of a signal on the radio frequency channel based exclusively on the trace, the determinant and a threshold value T. The invention also includes a cognitive radio which includes a radio receiver configured to detect an RF signal and at least one computer processing device for performing the above-described method.

Abstract: Expandable transceivers and receivers support operation on multiple frequency bands and multiple carriers. In an exemplary design, an apparatus (e.g., a wireless device, an integrated circuit (IC) chip, or circuit module) includes a low noise amplifier (LNA) and interface circuit. The LNA resides on an IC chip and includes a first/on-chip output and a second/off-chip output. The interface circuit also resides on the IC chip, is coupled to the second output of the LNA, and provides an amplified RF signal outside of the IC chip. The apparatus may further include a buffer, load circuit, and downconverter circuit. The buffer resides on the IC chip, is coupled to the first output of the LNA, and receives a second amplified RF signal from outside of the IC chip. The load circuit is coupled to the first output of the LNA. The downconverter circuit is coupled to the load circuit.

Abstract: A communication device having a wireless communication system and a Near Field Communication (NFC) circuit is provided. The NFC circuit includes two pads, two ferrite beads and a NFC controller. The first pad and the second pad are coupled to a NFC antenna. The first and the second ferrite bead are respectively coupled to the first pad and the second pad. The NFC controller includes two pins. The first pin and the second pin are coupled to the first ferrite bead and the second ferrite bead, respectively. The first pin and the second pin output a differential NFC signal to be emitted by the NFC antenna. The first and the second ferrite bead allow the fundamental frequency component of the NFC signal to pass, and filter out a plurality of high-frequency components for avoiding the operating frequency of the wireless communication system from being interfered by the high-frequency components.

Abstract: An NFC-enabled device including tag emulation circuitry and reader emulation circuitry operates so as to provide a signal strength meter function. The signal strength meter function, in tag emulation mode, measures and reports on how well the tag is coupled to a third party reader field. In reader emulation mode, the signal strength meter function measures and reports how well the reader of the NFC-enabled device couples to a tag that is being read. One exemplary method includes detecting an NFC reader field, operating reader receiver circuitry at the NFC-enabled device so as to at least determine the strength of a signal received from the reader field, generating information representative of the determined strength of the signal received from the reader field at a first time, and performing one or more predetermined actions based at least in part on the one or more signals representative of the determined strength.

Abstract: A system and methods for cancelling transmission leakage signals in a wide bandwidth Distributed Antenna System (“DAS”) having remote units is disclosed. An internal cancellation circuit within the remote unit is employed to reduce the transmitted leakage signals by generating a cancellation signal. This cancellation signal is added to the received signal to cancel the transmission leakage signal in the receiving signal path. A pilot signal generation circuit is employed to optimize the cancellation circuit operating parameters. The frequency of the pilot signal is swept over a range to determine the pilot frequency having the highest electromagnetic coupling. The amplitude and phase of the cancellation signal is then optimized to minimize the level of transmission leakage in the receiving transmission path.

Abstract: A light weight transmission device providing an identification signal is disclosed. In one aspect, the device comprises a gating device for controlling the transfer of information to the transmitter, a data retaining device, in communication with the gating device, receiving and storing the information for a known period of time, and a controller, in communication with the gating device, providing a signal to the gating device to enable transfer of the retained information to the transmitter at a known time and for a known period of time.

Abstract: RFID tags, tag circuits, and methods are provided that reject at least in part the distortion caused to wireless signals by interference in the environment. When the received RF wave is converted into an unfiltered input (971), a filtered output (972) is generated that does not include an artifact feature deriving from the distortion. The filtered output is used instead of the unfiltered input, which results in tag operation as if there were less interference in the environment, or none at all.

Abstract: The invention relates to a test device for testing the transmission quality of radio devices by integrating a noise generating device in the transmission chain of the test device. To this end, data to be transmitted are imaged on individual partial data streams modulated onto signals associated with the partial data streams and having different carrier frequencies. At this point in the transmission chain, a noise proportion for at least a part of the signals is added to one signal each of a carrier frequency, in order to allow frequency-selective control of the noise proportions added to the signals of the carrier frequencies. The resulting noisy signals and non-noisy signals of the carrier frequencies are transmitted by a transmission device, and a response signal sent back by a radio device to be tested is received by a receiving device. An analysis device evaluates the received response signal.

Abstract: A process for eliminating interference in a telecommunications network including a multi-beam satellite, a coverage area made up of a plurality of cells in which terminals are located, at least two of the cells, referred to as the first and second cell, being associated with the same frequency band, a first earth station including a first demodulator capable of demodulating signals transmitted by terminals located in the first cell and a second earth station including a second demodulator different from the first demodulator capable of demodulating signals transmitted by terminals located in the second cell. The process uses information supplied by the terminal, particularly its position and transmission parameters, and enables the appropriate G/T figure to be deduced. This information is then transmitted to the demodulator of the second earth station and will be used to reconstruct the signal incorporating the message and remove it from the received signal.

Abstract: Certain aspects of a method and system for providing wireless communication may include a single integrated circuit (IC) that handles communication for at least a Bluetooth (BT) connection and a Wireless Local Area Network (WLAN) connection by controlling transmission of acknowledgement signals based on a measured voice quality for one or both of the BT connection and the WLAN connection. The transmission of the acknowledgement signals communicated from the mobile station to an access point may be controlled. A BT priority signal may be asserted if data to be transmitted comprises high quality voice (HV3) data. The transmission of the acknowledgement signals may be controlled by raising a priority of an asserted WLAN priority signal higher than a priority of the asserted BT priority signal. The voice data may be transmitted via high quality voice (HV3) frames over the BT connection based on the asserted WLAN priority signal.

Abstract: A mobile device peripheral that incorporates a repeater antenna inside of a protective case for a mobile device to extend the range of short-range communications while minimizing interference caused by the thickness or materials of the protective case. The repeater antenna can be capable of receiving a wireless signal from an antenna in the mobile device and transmitting the same signal or an amplified version of the same signal. The repeater antenna can be capable of receiving a wireless signal from an external antenna and transmitting the same signal or an amplified version of the same signal to the mobile device. The mobile device peripheral can also include a battery that provides additional power the mobile device. Without a repeater antenna, the materials and/or thickness of the additional battery and/or the case can partially or completely block a short-range, low-frequency, or low-power communication signal such as Near Field Communication (NFC).

Abstract: A near field communications (NFC) device is disclosed that load modulates and regulates a radio frequency (RF) signal. The NFC device includes a rectifier that rectifies the RF signal to provide a direct current voltage. The NFC device also includes a modulator that modulates a data signal. The modulator provides a first voltage when the data signal is at a first level and provides a second voltage when the data signal is at a second level. The NFC device utilizes a regulator to regulate and to load modulate the RF signal. The regulator adjusts an impedance based upon a comparison of the DC voltage provided by the regulator to the first voltage provided by the modulator for the data signal at the first level or to the second voltage provided by the modulator for the data signal at the second level.

Abstract: An interface for connects a mobile phone and a plain old telephone service (POTS) phone. The interface detects a ring tone from a speaker output of the mobile phone and in response places a POTS ring signal on a ring line of the POTS phone. Upon a change in state of a hook signal, a hook state detector places a predetermined signal on a microphone input of the mobile phone.

Abstract: Power consumption of near-field communication devices is regulated by waking the device for communications when a potential external near-field device is detected, and by adjusting the resonant antenna circuit to account for the detected change in antenna environment. Such near-field communication devices include a resonant loop antenna circuit. The resonant loop antenna circuit is connected to an integrated circuit that includes a controller for controlling near-field communications via the resonant loop antenna circuit, an inductance detection circuit to detect changes in the antenna inductance, a wake-on circuit responsive to a sufficient change in antenna inductance to transition the controller from a low power sleep mode to a communications mode, and an antenna tuning circuit to adjust the variable component of the resonant loop antenna circuit to compensate for changes in antenna inductance and to maintain the target range of operation.

Abstract: Radio frequency test systems for characterizing antenna performance in various radio coexistence scenarios are provided. In one suitable arrangement, a test system may be used to perform passive radio coexistence characterization. During passive radio coexistence characterization, at least one signal generator may be used to feed aggressor signals directly to antennas within an electronic device under test (DUT). The aggressor signals may generate undesired interference signals in a victim frequency band, which can then be received and analyzed using a spectrum analyzer. During active radio coexistence characterization, at least one radio communications emulator may be used to communicate with a DUT via a first test antenna. While the DUT is communicating with the at least one radio communications emulator, test signals may also be conveyed between DUT 10 and a second test antenna. Test signals conveyed through the second test antenna may be used in obtaining signal interference level measurements.

Abstract: A system for communicating between a first unit and a second unit without a physical connection, the system including a magnetic element for creating a magnetic field, a sensor operatively arranged to detect changes in the magnetic field, and a driver operatively arranged to alter the magnetic field detected by the sensor in accordance with a first signal, the first signal operatively arranged to transmit data independent of an amplitude of the first signal, the sensor generating a second signal in response to changes in the magnetic field, the second signal representative of the first signal.

Abstract: A circuit for amplifying radio frequency signals comprising: a terminal for connection to an antenna; a common amplifier arranged in a common-gate configuration between a first node and said terminal; a transmit amplifier operable to amplify a radio frequency signal present at an input node and provide the amplified signal to said first node; and a receive amplifier operable to amplify a radio frequency signal present at said first node and provide the amplified signal to an output node; wherein the circuit is operable in two modes: in a receive mode, the common and receive amplifiers being configured so as to together form a receive cascode for amplifying radio frequency signals received at the terminal; and in a transmit mode, the common and transmit amplifiers being configured so as to together form a transmit cascode for amplifying radio frequency signals applied at the input node.

Abstract: A wireless communication system may include a wireless access point including a first wireless transceiver and a controller associated therewith and providing wireless communications within a defined space having an entrance, and mobile wireless communications devices, each including a first near field communications (NFC) device and a second wireless transceiver communicating with the first wireless transceiver. The wireless communication system may also include a second NFC device adjacent the entrance of the defined space, and a third NFC device within the defined space. The controller may permit wireless communications of a given mobile wireless communications device with the wireless access point based upon communication of the corresponding first NFC device with the second and third NFC devices.

Abstract: A system for delivering data to a user includes a beverage container provided with an electronic device having an electronic display, and a portable electronic apparatus such as an electronic mobile phone or an electronic tablet, so that a user operates the portable electronic apparatus to compose data, which are transmitted via ultra-sound to the beverage container and displayed on its electronic display.

Abstract: Exemplary embodiments are directed to a coexistence of NFC and wireless power functionalities. A device may include an antenna configured to receive a signal. The device may further include a communication circuit configured to selectively couple to the antenna in a default mode of operation. The device may further include a wireless power circuit configured to selectively couple to the antenna in response to detecting that the signal is provided to power or charge a load.