Abstract: Techniques described herein provide cancelation of cross-polarization interference during simultaneous receipt of radiofrequency signals (e.g., an X-signal and a Y-signal) in a same frequency channel in nominally orthogonal polarizations. Though nominally orthogonally polarized, each signal contributes some cross-polarization interference to the other. Embodiments receive and demodulate each signal by a corresponding demodulator to generate corresponding X-symbol and Y-symbol decision signals, referenced to a common clock domain. An X-channel adaptive canceler (X-CAC) generates an X-output signal by using one or more Y-symbol decision signals adaptively to cancel cross-polarization interference from the Y-signal, and a Y-CAC generates a Y-output signal by using one or more X-symbol decision signals adaptively to cancel cross-polarization interference from the X-signal (e.g., the X-CAC and the Y-CAC each using a first-order least mean squares control loop).

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer-storage media, for compensating for frequency-dependent I-Q imbalance. In some implementations, a radio receiver includes an in-phase mixer configured to generate an in-phase (I) signal and a quadrature mixer configured to generate a quadrature (Q) signal. A first analog-to-digital (A/D) converter is configured to generate first digital samples from one of the I signal and the Q signal. A second analog-to-digital (A/D) converter is configured to generate second digital samples from the other of the I signal and the Q signal. A compensation system includes a feedback loop configured to compensate for frequency-dependent I-Q imbalance based on results, for each of multiple of the first digital samples, of cross-correlation of the first digital sample with each of multiple of the second digital samples.

Abstract: Systems and methods are described, and one method includes allocate a continuous duration within a TDMA scheme, for asynchronous NOMA transmissions, and extending from an allocation start time to an allocation termination time, formed of contiguous time slots of the TDMA scheme, and included providing to asynchronous NOMA user terminals an indication of the allocation start time and termination time, indicating allowance to perform asynchronous NOMA transmissions within a start time constraint that starts of the asynchronous NOMA transmissions do not precede the allocation start time, and terminations of the asynchronous NOMA transmissions do not succeed the allocation termination time.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer-storage media, for compensating for frequency-dependent I-Q imbalance. In some implementations, a radio receiver includes an in-phase mixer configured to generate an in-phase (I) signal and a quadrature mixer configured to generate a quadrature (Q) signal. A first analog-to-digital (A/D) converter is configured to generate first digital samples from one of the I signal and the Q signal. A second analog-to-digital (A/D) converter is configured to generate second digital samples from the other of the I signal and the Q signal. A compensation system includes a feedback loop configured to compensate for frequency-dependent I-Q imbalance based on results, for each of multiple of the first digital samples, of cross-correlation of the first digital sample with each of multiple of the second digital samples.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer-storage media, for compensating for frequency-dependent I-Q imbalance. In some implementations, a radio receiver includes an in-phase mixer configured to generate an in-phase (I) signal and a quadrature mixer configured to generate a quadrature (Q) signal. A first analog-to-digital (A/D) converter is configured to generate first digital samples from one of the I signal and the Q signal. A second analog-to-digital (A/D) converter is configured to generate second digital samples from the other of the I signal and the Q signal. A compensation system includes a feedback loop configured to compensate for frequency-dependent I-Q imbalance based on results, for each of multiple of the first digital samples, of cross-correlation of the first digital sample with each of multiple of the second digital samples.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer-storage media, for compensating for frequency-dependent I-Q imbalance. In some implementations, a radio receiver includes an in-phase mixer configured to generate an in-phase (I) signal and a quadrature mixer configured to generate a quadrature (Q) signal. A first analog-to-digital (A/D) converter is configured to generate first digital samples from one of the I signal and the Q signal. A second analog-to-digital (A/D) converter is configured to generate second digital samples from the other of the I signal and the Q signal. A compensation system includes a feedback loop configured to compensate for frequency-dependent I-Q imbalance based on results, for each of multiple of the first digital samples, of cross-correlation of the first digital sample with each of multiple of the second digital samples.

Abstract: Systems and methods are described, and one method includes allocate a continuous duration within a TDMA scheme, for asynchronous NOMA transmissions, and extending from an allocation start time to an allocation termination time, formed of contiguous time slots of the TDMA scheme, and included providing to asynchronous NOMA user terminals an indication of the allocation start time and termination time, indicating allowance to perform asynchronous NOMA transmissions within a start time constraint that starts of the asynchronous NOMA transmissions do not precede the allocation start time, and terminations of the asynchronous NOMA transmissions do not succeed the allocation termination time.

Abstract: Signals are received that include a channel band and an adjacent band. The channel band is demodulated to obtain recovered symbols. Cross-correlation between the recovered symbols and the adjacent band is estimated. Adjacent channel interference is estimated, using the estimated cross-correlation of the recovered symbols and the adjacent band. Upon the estimated adjacent channel interference meeting a condition, a back-off command is sent to a transmitter power amplifier.

Abstract: Signals are received that include a channel band and an adjacent band. The channel band is demodulated to obtain recovered symbols. Cross-correlation between the recovered symbols and the adjacent band is estimated. Adjacent channel interference is estimated, using the estimated cross-correlation of the recovered symbols and the adjacent band. Upon the estimated adjacent channel interference meeting a condition, a back-off command is sent to a transmitter power amplifier.

Abstract: An analog TV system includes a transmitter which produces a horizontal unique pulse sequence during each horizontal blanking interval. The pulse sequence is amplitude modulated between two levels to define a horizontal unique word for horizontal synchronization. The frequency of the pulse sequence is selected for use by the receiver section as the color subcarrier phase reference. The average level of the pulse sequence is set at the transmitter and used at the receiver for DC restoration in a clamping circuit. The peak amplitude of the pulses of the pulse sequence define a reference level against which a receiver produced local reference is compared for AGC.

Abstract: An analog TV system includes a transmitter which produces a horizontal unique pulse sequence during each horizontal blanking interval. The pulse sequence is amplitude modulated between two levels to define a horizontal unique word for horizontal synchronization. The frequency of the pulse sequence is selected for use by the receiver section as the color subcarrier phase reference. The average level of the pulse sequence is set at the transmitter and used at the receiver for DC restoration in a clamping circuit. The peak amplitude of the pulses of the pulse sequence define a reference level against which a receiver producing local reference is compared for AGC.

Abstract: A cipher system in which a key is initially inserted into a shift register and the serial output of the shift register is added to the plain text message and the sum is fed back into the serial input of the shift register. Parallel outputs of the shift register are led to a logic function which transforms the multiple inputs into a single output, the value of which is evenly distributed among the possible combinations on the input. The logic function output is then added to the message to produce the enciphered message. In the decipherer, the deciphered message is added to the serial output of the shift register to produce the serial input to the shift register. Otherwise, the decipherer closely resembles the encipherer.

Abstract: A method and apparatus for one-way subscription television service control which allows the subscribers to subscribe in advance to a variety of programming or to select programming oa a pay-per-view basis.