Abstract: A headset includes a Bluetooth headset body, a microphone, and at least one speaker. The Bluetooth headset body includes a Bluetooth headset main-board and a battery. Interfaces provided by the Bluetooth headset main-board include the interfaces for the microphone and the speaker. Anodes of the microphone and the at least one speaker are connected to the corresponding interfaces of the Bluetooth headset main-board, respectively, and their cathodes are connected to a ground cable, respectively. The headset further includes: a headset plug, where interfaces of the headset plug are correspondingly and electrically connected to the anode of the at least one speaker, the ground cable, and the anode of the microphone, respectively; and connections between the anode of the microphone and of the at least one speaker and the corresponding interfaces of the Bluetooth headset main-board are disconnected after the headset plug is plugged in the external headset jack.

Abstract: A method is described that enables maximum-likelihood (ML) demodulation for MIMO communications over frequency-selective channels. An equalizer is typically employed to suppress inter-symbol interference (ISI) due to frequency-selectiveness of the channel, but the noise of the equalizer output can be highly correlated such that standard ML-MIMO demodulations cannot directly apply. The method comprises first constructing equivalent post-equalization MIMO channel and noise covariance matrix, and then de-correlating the equalizer output so that ML or near-ML MIMO demodulations can be applied to improve the performance. Additionally, successive ISI cancellation (SIC) is described for further performance improvement.

Abstract: Methods and apparatus of channel estimation using time-domain parameter extraction are disclosed. The wireless channel can be modeled by a multipath model with a limited number of parameters in the continuous time domain. In the discrete time domain, the multipath model leads to channel impulse responses that have a limited number of channel taps with non-negligible energy. Extracting the time-domain parameters and then reconstructing the channel yields channel estimates that have better accuracy. Time-domain parameter extraction also has lower computational complexity than existing methods.

Abstract: A wireless telecommunication device conducts base station pages at large intervals, such as 30 seconds, rather than the more conventional 0.5 to 4 seconds. The network processes calls placed to that telecommunication device in accordance with an SMS (Short Messaging Service) type protocol rather than a conventional voice call protocol. Particularly, the network sends an SMS to the telephone indicating that a third party is calling (hereinafter termed a “pre-call SMS”). The pre-call SMS indicates the telephone number of the third party. The user of the telephone may call the third party back. In accordance with this protocol, the need to page at very short intervals so as to permit a telephone call to be established in “real-time” is eliminated. Therefore, the paging interval can be increased substantially, thereby substantially prolonging battery charge lifetime of the telephone.

Abstract: Multipoint broadcasting requires that the downlink-channel information be available at collaborating base stations. Methods and apparatus for wideband analog channel feedback are described that provide downlink-channel information feedback from mobile users to base stations via uplink channels, and that use very few or no resources of the RAT of the wireless cellular network. Also described are methods and apparatus that perform channel-feedback signal cancellation at base stations to reduce its interference on the uplink-traffic signal. Wideband analog channel feedback is adaptable to the feedback bandwidth in uplink, and it offers frequency diversity to combat the deep fading in feedback channels. Wideband analog channel feedback is also applicable to uplink channel-information feedback. Applications of the described methods and apparatus include multipoint broadcasting in a wireless cellular network, and more generally, channel feedback between two communicating devices in a communications network.

Abstract: A headset includes a Bluetooth headset body, a microphone, and at least one speaker. The Bluetooth headset body includes a Bluetooth headset main-board and a battery. Interfaces provided by the Bluetooth headset main-board include the interfaces for the microphone and the speaker. Anodes of the microphone and the at least one speaker are connected to the corresponding interfaces of the Bluetooth headset main-board, respectively, and their cathodes are connected to a ground cable, respectively. The headset further includes: a headset plug, where interfaces of the headset plug are correspondingly and electrically connected to the anode of the at least one speaker, the ground cable, and the anode of the microphone, respectively; and connections between the anode of the microphone and of the at least one speaker and the corresponding interfaces of the Bluetooth headset main-board are disconnected after the headset plug is plugged in the external headset jack.

Abstract: Methods and apparatus of channel feedback are disclosed. In OFDM systems, the channel is acquired in the frequency domain. A generic multipath model for wireless channels, however, reveals that the time-domain parameters of the channel require much smaller data than the frequency-domain representation of the channel. Means to extracting the time-domain parameters from the frequency-domain channel samples are described for both the continuous time domain and the discrete time domain. Refinements of the time-domain parameters via minimizing a frequency-domain matching error are also described, which further improve the quality of the channel feedback and reduce the feedback overhead. Channel feedback with the time-domain parameters requires only a small fraction of the feedback overhead that is needed by existing channel feedback schemes, and maintains consistently superior performances over wireless channels of various delay spreads, short or long.

Abstract: Multipoint broadcasting requires the base stations to be phase-synchronized. Methods and apparatus are described that provide phase synchronization of base stations with the downlink-channel phase feedback by mobile users. Also described are methods and apparatus that make phase synchronization of base stations independent of multipoint-broadcast sessions, thus reducing the synchronization overhead and improving network capacity. The methods and apparatus utilize model-based downlink-channel phase feedback that reduces most of the feedback overhead. Applications of the described methods and apparatus include wireless multipoint broadcast systems, also known as coordinated multipoint transmission, or CoMP, in LTE-A (long-term evolution, advanced) systems, and frequency and phase synchronization of a cluster of base stations, or more generally, of a cluster of wireless devices.

Abstract: A method, a system, and an apparatus for creating a Content-on-Demand (CoD) service are disclosed herein. The method includes receiving a Session Initiation Protocol (SIP) service request sent by a User Equipment (UE); converting the SIP service request into a Real-Time Streaming Protocol (RTSP) service request, and sending the RTSP service request to a server; receiving an RTSP service response sent by the server; and converting the RTSP service response into a SIP service response, and sending the SIP service response to the UE to create the CoD service between the UE and the server.

Abstract: Large-dimension MIMO and multipoint broadcasting in new generation of wireless networks create high demand for various types of pilots in transmission signals for channel estimation, data demodulation, synchronization, etc. More pilots, as in existing networks, use more resources and thus diminish the network capacity. Methods and apparatus of heterogeneous pilots are disclosed. A heterogeneous pilot has its own signal characteristics that are different from the primary information-bearing signals in the network. Heterogeneous pilots can be spread-spectrum signals in an OFDM-based wireless network. Heterogeneous pilots use no network resources, and can be as many as desired, and can be designed to have versatile utilities. Also described are methods and apparatus of heterogeneous pilot cancellation that minimizes the interference of heterogeneous pilots on the primary information-bearing signals.

Abstract: Multipoint broadcasting requires that the downlink-channel information be available at collaborating base stations. Methods and apparatus for wideband analog channel feedback are described that provide downlink-channel information feedback from mobile users to base stations via uplink channels, and that use very few or no resources of the RAT of the wireless cellular network. Also described are methods and apparatus that perform channel-feedback signal cancellation at base stations to reduce its interference on the uplink-traffic signal. Wideband analog channel feedback is adaptable to the feedback bandwidth in uplink, and it offers frequency diversity to combat the deep fading in feedback channels. Wideband analog channel feedback is also applicable to uplink channel-information feedback. Applications of the described methods and apparatus include multipoint broadcasting in a wireless cellular network, and more generally, channel feedback between two communicating devices in a communications network.

Abstract: An article includes a layer of graphene having a first work function; and a metal oxide film disposed on the layer of graphene, the metal oxide film having a second work function greater than the first work function. Electrons are transferred from the layer of graphene to the metal oxide film, forming a hole accumulation layer in the layer of graphene.

Abstract: A method and apparatus are disclosed for detecting a pilot signal in a wireless receiver using coherent combining/noncoherent detection techniques. Coherent combining/noncoherent detection techniques are used to detect the pilot signal whenever the receiver is already frequency locked, or otherwise known to have a small frequency offset Conventional noncoherent combining/noncoherent detection techniques are utilized to initially acquire the timing of the forward channel. Once the receiver is frequency locked, coherent combining/noncoherent detection techniques may be used to continuously detect the pilot signals. After the receiver is frequency locked, the residue frequency error is small over several consecutive correlator outputs The correlator outputs can thus be combined coherently (since the frequency error is known to be small), and the phase dependency is then eliminated by noncoherent detection.

Abstract: Multipoint broadcasting requires the base stations to be phase-synchronized. Methods and apparatus are described that provide phase synchronization of base stations with the downlink-channel phase feedback by mobile users. Also described are methods and apparatus that make phase synchronization of base stations independent of multipoint-broadcast sessions, thus reducing the synchronization overhead and improving network capacity. The methods and apparatus utilize model-based downlink-channel phase feedback that reduces most of the feedback overhead. Applications of the described methods and apparatus include wireless multipoint broadcast systems, also known as coordinated multipoint transmission, or CoMP, in LTE-A (long-term evolution, advanced) systems, and frequency and phase synchronization of a cluster of base stations, or more generally, of a cluster of wireless devices.

Abstract: Methods and apparatus are described that provide efficient detection of the carrier-phase difference (CPD) between communicating devices over the entire signal bandwidth. The CPD detection utilizes the linear structure of the CPD, which eliminates most of the feedback overhead. Both feedback mechanisms, compact digitized feedback, and feedback via fast signaling protocols, are described. The CPD can be decomposed into a fixed/slow-changing portion and a fast-varying portion, with the former being pre-calibrated and communicated prior to communications sessions, thus further reducing the feedback overhead and improving the CPD detection accuracy. The nonlinearity in the TX/RX chains can also be pre-calibrated, allowing CPDs with more general structures to be detected by methods that detect CPDs with linear structures.

Abstract: A description is given of an apparatus that includes a division unit configured to receive a data stream and to divide the received data stream into a plurality of data segments. The apparatus further includes a plurality of first CRC check units, wherein each of the first CRC check units is configured to perform a first CRC check of a respective one of the plurality of data segments, the plurality of first CRC checks being performed concurrently, and wherein each of the first CRC check units is configured to perform a second CRC check based on an output of the respective first CRC check unit.

Abstract: A method is described that enables maximum-likelihood (ML) demodulation for MIMO communications over frequency-selective channels. An equalizer is typically employed to suppress inter-symbol interference (ISI) due to frequency-selectiveness of the channel, but the noise of the equalizer output can be highly correlated such that standard ML-MIMO demodulations cannot directly apply. The method comprises first constructing equivalent post-equalization MIMO channel and noise covariance matrix, and then de-correlating the equalizer output so that ML or near-ML MIMO demodulations can be applied to improve the performance. Additionally, successive ISI cancellation (SIC) is described for further performance improvement.

Abstract: Methods and apparatus are described that provide carrier-phase difference (CPD) acquisition via signaling protocols between communicating devices. The random CPD between two disjoint devices can be measured by the signaling protocols described herein. With the availability of the CPD, a device is also able to acquire its outgoing channel (transmit channel) information, thus avoiding the channel information feedback that is being considered and/or practiced in some wireless communications systems. Also described are methods and apparatus that use the CPD to synchronize the clocks of two or more devices and that track the time-variations of the CPD for reliable CPD measurement and tracking loop operations. Applications of the described methods and apparatus include wireless multipoint broadcast systems, also known as coordinated multipoint transmission, or CoMP, in LTE (long-term evolution)-advanced systems, point-to-point wireless MIMO systems, and general wireless device networks.

Abstract: A description is given of an apparatus that includes a division unit configured to receive a data stream and to divide the received data stream into a plurality of data segments and a plurality of first CRC check units, wherein each of the first CRC units is configured to perform a CRC check of a respective one of the plurality of segments of data, and wherein the plurality of CRC checks are performed concurrently.