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). The resulting X-output signal and Y-output signal can be further decoded and output by the receiver to downstream systems and/or components.

The present invention relates to a method and an apparatus for processing a signal, which are used for effectively reproducing a multimedia signal, and more particularly, to a method and an apparatus for processing a signal, which are used for implementing filtering for multimedia signal having a plurality of subbands with a low calculation amount. To this end, provided are a method for processing a multimedia signal including: receiving a multimedia signal having a plurality of subbands; receiving at least one proto-type filter coefficients for filtering each subband signal of the multimedia signal; converting the proto-type filter coefficients into a plurality of subband filter coefficients; truncating each subband filter coefficients based on filter order information obtained by at least partially using characteristic information extracted from the corresponding subband filter coefficients, the length of at least one truncated subband filter coefficients being different from the length of truncated subband filter coefficients of another subband; and filtering the multimedia signal by using the truncated subband filter coefficients corresponding to each subband signal and an apparatus for processing a multimedia signal using the same.

A precision frequency monitor provides a precision frequency monitor value (PFM) indicative of the precision of the frequency or period of an input reference signal. A first averaging module is responsive to the input reference signal to find an average frequency or period during successive predetermined time periods defining operational cycles. A second averaging module is responsive to an output of the first averaging module to average the output of the first averaging module over N operational cycles, where N is an integer, and output an updated PFM value every N operational cycles. An infinite impulse response (IIR) filter is responsive to the output of the first averaging module to filter the output of the first averaging module to output interim updated PFM values within each sequence of N operational cycles.

From a mixed signal in which a first signal and a second signal are mixed, the second signal is removed at low processing cost and without delay. As a result, an estimated first signal which has low residue of the second signal and low distortion is obtained. An estimated first signal is generated by subtracting a pseudo second signal which is estimated to be mixed in a first mixed signal in which a first signal and a second signal are mixed from the first mixed signal. The pseudo second signal is obtained by a first adaptive filter using a second mixed signal in which the first signal and the second signal are mixed in a different proportion from the first mixed signal. A coefficient update amount of the first adaptive filter is made smaller as compared with a case when the estimated first signal is smaller than the first mixed signal, in case the estimated first signal is larger than the first mixed signal.

A digital filter circuit is described. The digital filter circuit includes a digital filter input, at least two finite impulse response (FIR) filter circuits, and a connection circuit. The digital filter input is configured to receive a digital input signal set having a data parallelism. The at least two FIR filter circuits are configured to process the digital input signal set at least partially. The at least two FIR filter circuits include a pre-adder sub-circuit, a convolution sub-circuit, and a post-adder sub-circuit, respectively. The connection circuit is configured to selectively connect the at least two FIR filter circuits based on the data parallelism of the digital input signal set.

An acoustic response monitor. The acoustic response monitor includes a speaker, a microphone, and a response analyzer in electrical communication with the speaker and the microphone. The speaker is configured to generate a sound in response to an excitation signal. The microphone is configured to generate a microphone signal in response to a sound. The response analyzer is configured to generate an adaptive filter to minimize a difference between the excitation signal as modified by the adaptive filter and the microphone signal. The response analyzer may be configured to determine a difference between the adaptive filter and a previously generated adaptive filter. The response analyzer may be configured to trigger an alarm if the difference exceeds a predetermined threshold.

Disclosed is a mechanism for reducing noise caused by an analog to digital conversion in a test and measurement system. An adaptive linear filter is generated based on a converted digital signal and measured signal noise. The adaptive linear filter includes a randomness suppression factor for alleviating statistical errors caused by a comparison of a signal circularity coefficient and a noise circularity coefficient in the adaptive linear filter. The adaptive linear filter is applied to the digital signal along with a stomp filter and a suppression clamp filter. The digital signal may be displayed in a complex frequency domain along with depictions of the adaptive linear filter frequency response and corresponding circularity coefficients. The display may be animated to allow a user to view the signal and/or filters in the frequency domain at different times.

A reconfigurable sensor monitoring system includes software tunable filters, each of which is programmable to condition one type of analog signal. A processor coupled to the software tunable filters receives each type of analog signal so-conditioned.

There is a need to monitor and control the state of relays and circuit breakers within power distribution systems. The monitoring of a relay state, i.e. open or closed, is often performed by applying a monitoring signal to sensing contacts added to the relay. Manufactures of such systems have chosen many different voltages for their own. monitoring systems making it difficult to interconnect dissimilar monitoring systems. A signal conditioning circuit is provided that can cope with a large input voltage range and can be configured to allow may items of equipment(which may be new item or legacy items) to be connected to a controller.

A digital quadrature modulator holds local oscillator circuitry configured to provide local oscillator signals, and local oscillator polarity logic circuitry configured to select an In-phase and a Quadrature local oscillator signal according to a sign bit of an In-phase control word and a sign bit of a Quadrature control word, respectively. The modulator holds a number of local oscillator control logic circuits, each configured to generate a conditioned signal by gating one or both of the selected local oscillator signals according to values of the In-phase control word and/or values of the Quadrature control word. The modulator has one or more sets of switched-capacitor units, where each unit has an output provided by an output capacitor, and where a signal at the input side of the output capacitor is controlled by a conditioned signal. The outputs of at least two of the switched-capacitor units are combined in a common node.