Abstract: A method and an apparatus for determining validity of samples for a digital pre-distortion apparatus is disclosed. It is an object of at least one embodiment to provide a method and an apparatus for determining validity of samples for a digital pre-distortion apparatus that is configured to compensate for nonlinearity of a power amplifier in an efficient manner by accurately estimating a pre-distortion coefficient with a low-capacity memory.

Abstract: The present invention relates to a transmission method for network management control information and a microwave device, where the method includes: receiving, by a first device, network management control information, where the network management control information is microwave parameter configuration information of a second device; generating, by the first device, a control signal according to the network management control information, and generating a to-be-sent radio frequency signal after baseband processing and radio frequency processing are performed on preset information; and performing, by the first device, modulation on the radio frequency signal by using the control signal, to obtain a parameter configuration signal, and sending the parameter configuration signal to the second device.

Abstract: A system and method for compensating for detected phase errors during communications between synchronized devices. In an embodiment, the two devices may be a touch screen device and a synchronized stylus device. To this end, the touch screen device includes a controller configured to receive data signals from the stylus at specific time intervals. The touch screen device generates an internal control signal for receiving the incoming data signals at an expected frequency. The touch screen device further includes circuitry for measuring differences in the time a data signal is actually received against when the data signal was expected to be received and determines a time difference (e.g., a phase error). Then, the internal control signal may be adjusted to compensate for the accumulated phase error. Such a measurement and compensation helps ensure that communications remain in synchronization without having to reestablish synchronization through a cumbersome synchronization process.

Abstract: An apparatus and associated methodology providing read channel circuitry having a signal equalizer that sends an equalized signal to a bit detector. The read channel circuitry is capable of sampling values of the equalized signal to identify a bit transition from among a predefined plurality of different bit transitions. The apparatus may have channel optimization (CO) logic that, based on the input signal and the sampling of the equalized signal, defines first values for a programmable parameter of the bit detector that substantially maximizes vector separations among vectors of waveform target samples corresponding to the predefined plurality of different bit transitions, while the CO logic also defines second values for a programmable parameter of the equalizer that substantially minimizes the mean squared separation of the equalized signal segment for each bit transition from the waveform target corresponding to that bit transition.

Abstract: A method for accessing aircraft interference path loss in an aircraft. A plurality of radio frequency signals that are stepped through a plurality of frequencies in a frequency range is transmitted from a plurality of locations within an interior of the aircraft. Radio frequency signals present at a receive antenna are received in response to transmitting the plurality of radio frequency signals to form a plurality of measurements. An average of averages curve is generated from the plurality of measurements. A peak to average ratio is identified. Field uniformity is identified. A standard error for the average of averages curve is determined. An upper bound for the aircraft interference path loss in the aircraft is predicted using the average of averages curve, the peak to average ration, the field uniformity, and the standard error.

Abstract: Methods and systems for performing compressed time domain joint channel estimation in a multi-user MIMO LTE wireless network include receiving training signals from a plurality of users, estimating a maximum delay spread for the received data according to a coherence bandwidth of the received data, limiting the received data in the time domain to the estimated maximum delay spread, selecting and estimating an active tap from the limited data set, and subtracting a contribution of the selected active tap from the reduced data set. These steps can be repeated until the residual signal falls below a specified minimum. The network can be a C-RAN network. The training data can be SRS or DMRS data. Limiting the received data ensures that only a few significant taps are analyzed, so that the system is not under determined and can be analyzed for accurate channel estimation using any of several existing algorithms.

Abstract: Aspects of the subject disclosure may include, for example, a system for receiving first electromagnetic waves via a transmission medium without utilizing an electrical return path, and inducing second electromagnetic waves at an interface of the transmission medium without the electrical return path. In an embodiment, the first and second electromagnetic waves have a non-optical frequency range. Other embodiments are disclosed.

Abstract: A method and an apparatus for transmitting broadcast signals thereof are disclosed. The apparatus for transmitting broadcast signals, the apparatus comprises an encoder to encode service data corresponding to a number of physical paths, a time interleaver to time interleave the encoded service data in each physical path, a frame builder to build at least one signal frame including the time interleaved service data, a modulator to modulate data in the built at least one signal frame by an OFDM (Orthogonal Frequency Division Multiplex) scheme and a transmitter to transmitting the broadcast signals having the modulated data.

Abstract: Time-reversal wireless communication includes: at a base station, receiving a probe signal from a terminal device; generating a signature waveform that is based on a time-reversed signal of a channel response signal derived from the probe signal; performing quadrature amplitude modulation (QAM) on a transmit signal to generate a quadrature amplitude modulated signal; and generating a transmission signal based on the quadrature amplitude modulated signal and the signature waveform.

Abstract: A method for transporting communications signals includes receiving an analog IF signal at a first unit. The analog IF signal includes a first carrier having a first frequency and a first bandwidth and a second carrier having a second frequency different from the first frequency and a second bandwidth. The analog IF signal is converted to a digitally sampled IF signal having the first carrier located in a first Nyquist zone, the second carrier located in a second Nyquist zone, an image of the first carrier located in a third Nyquist zone, and an image of the second carrier located in the third Nyquist zone. The image of the first carrier and the image of the second carrier is transmitted from the first unit to a second unit, where the image of the first carrier and the image of the second carrier is then converted to the analog IF signal.

Abstract: A method and apparatus for efficient precoding matrix verification in a multiple-input multiple-output MIMO wireless communication system are disclosed. A wireless transmit/receive unit WTRU sends a precoding matrix index PMI to an eNodeB. The eNodeB sends a verification message including a PMI indicator indicating whether or not the PMI of the WTRU and a PMI of the eNodeB are identical. If the PMI of the WTRU and of the eNodeB are identical, the eNodeB sends just a PMI indicator otherwise the eNodeB sends to the WTRU a PMI indicator and the PMI of the eNodeB. A plurality of PMIs may be sent simultaneously, and the PMIs may be partitioned into a plurality of groups. The PMI indicator may be either attached to or inserted into control signaling. PMI validation messages can be signaled to WTRU by control signaling or use of a dedicated reference signal.

Abstract: A method of transmitting a data signal using an optical transmitter of an optical communications system. A first encoder processes an N-bit input vector in accordance with a first mapping to generate a corresponding M-bit data stream. A Forward Error Correction encoder processes the M-bit data stream in accordance with a predetermined FEC encoding scheme to generate an encoded signal. A constellation mapper maps the encoded signal to symbol values in accordance with a predetermined modulation scheme to generate a corresponding symbol stream. A modulator modulates a carrier light in accordance with the encoded symbol stream to generate an optical signal for transmission through the optical communications system. The first mapping can be adjusted to maximize performance of the optical communications system.

Abstract: Various embodiments of wireless communication systems and methods in which the system seamlessly dual-uses a receiver chain for incoming transmissions and for other signal sensing purposes. The system is configured such that there are multiple receiver chains, and at least one receiver chain alternates between receiving a communication signal with information payload and receiving other signals solely for the purposes of monitoring and/or improving some aspects of the system. In various embodiments, the alternating receiver chain receives alternatively signals with information payloads and signals which have passes through a power amplifier with amplifier distortion characteristics. In various embodiments, the alternating receiver chain receives alternatively signals with information payloads and signals which may be associated with background noise, or other radio transmissions.

Abstract: Monitoring devices and systems comprise a plurality of data channel modules coupled to processing circuitry. Each data channel module of the plurality of data channel modules is configured to capture wireless communications for a selected frequency channel. The processing circuitry is configured to receive captured wireless communications from the plurality of data channel modules and to organize received wireless communications according to at least one parameter. Related methods of monitoring wireless communications are also disclosed.

Abstract: Systems and methods presented herein provide for monitoring of noise and other interfering energy on a communication link. One system includes an interface coupled to the communication link to receive a signal conveyed over the communication link. The system also includes a monitor operable to: track energy across a frequency spectrum of the signal conveyed over the communication link for a predetermined period of time; flag, at intervals of the predetermined period of time, energy levels across the frequency spectrum of the signal that breach a threshold energy level to identify where in the frequency spectrum a breach of the threshold energy level occurs; and add the flags to determine how long the threshold energy level was breached during the predetermined period of time.

Abstract: A wireless device transmits a frame by determining a plurality of Resource Units (RUs) of the frame, providing pilots in a first RU of the frame at a first set of positions, providing pilots in a second RU of the frame at a second set of positions, and transmitting the frame. The first set of positions is different from the second set of positions. A wireless device receives a frame including an RU including pilots and processes the pilots. When an RU for the data symbol includes an odd-numbered lowest subcarrier, the pilots are included at a first set of positions in the resource unit. When the RU includes an even-numbered lowest subcarrier, the pilots are included at a second set of positions in the resource unit. The second set of positions is different from the first set of positions.

Abstract: Methods and devices related to channel estimation for a communication system comprising a plurality of communication connections are provided. For channel estimation, test sequences are used having three different elements, for example ?1, 0 and +1.

Abstract: A multi-input multi-output (MIMO) system considers either reliability for each antenna or a time/frequency location, and transmits a signal at an unequal ratio for each antenna according to the consideration result. The method for use in the MIMO system including multiple antennas includes processing a signal according to an unequal ratio transmission scheme employing the multiple antennas at an unequal ratio, and transmitting the processed signal via the multiple antennas.

Abstract: Techniques for processing a received multi-code code-division multiple-access (CDMA) signal to detect unused spreading codes are disclosed. An example method includes, for each of a plurality of observation time intervals and for each of one or more candidate spreading codes, determining a detection threshold for use in detecting whether the candidate spreading code is unused in the received multi-code CDMA signal, based on a target detection sensitivity and at least one of an estimate of received signal quality and an estimate of channel estimation quality. Estimated signal power for the candidate spreading code is compared to estimated noise and interference power corresponding to a spreading code that is known to be unused or corresponding to a spreading code that carries known symbol values, using the calculated detection threshold. Whether or not the candidate spreading code is unused is then determined, based on the comparison.

Abstract: The present invention provides a data transmission device and method in a wireless communication system. The device comprises a processor which is connected with the M antennas and which is formed so as to generate data to be transmitted through the M antennas, on the basis of a precoding matrix; the precoding matrix is generated based on a plurality of matrices; and a first matrix, which is one matrix among the plurality of matrices, is selected from within a codebook for N antennas (where N<M).