Abstract: There is provided a method of transcoding an Enhance Full Rate (EFR) 12.2 Kbps encoded frame into an Adaptive Multi-Rate (AMR) 12.2 Kbps encoded frame, where the method comprises receiving the EFR 12.2 Kbps encoded frame from a first codec; determining if the EFR 12.2 Kbps encoded frame is a Silence Insertion Descriptor (SID) frame; if the EFR 12.2 Kbps encoded frame is determined to be the SID frame, the method further comprises transcoding the EFR SID frame. There is also provided a method of transcoding an EFR 12.2 Kbps encoded frame into an AMR 12.2 Kbps encoded frame, where the method comprises receiving the AMR 12.2 Kbps encoded frame from a first codec; determining if the AMR 12.2 Kbps encoded frame is an SID frame; if the AMR 12.2 Kbps encoded frame is determined to be the SID frame, the method further comprises transcoding the AMR SID frame.

Abstract: There is provided a pitch lag predictor for use by a speech decoder to generate a predicted pitch lag parameter. The pitch lag predictor comprises a summation calculator configured to generate a first summation based on a plurality of previous pitch lag parameters, and a second summation based on a plurality of previous pitch lag parameters and a position of each of the plurality of previous pitch lag parameters with respect to the predicted pitch lag parameter; a coefficient calculator configured to generate a first coefficient using a first equation based on the first summation and the second summation, and a second coefficient using a second equation based on the first summation and the second summation, wherein the first equation is different than the second equation; and a predictor configured to generate the predicted pitch lag parameter based on the first coefficient and the second coefficient.

Abstract: Disclosed are various embodiments of a single ended laser driving circuit. One embodiment includes a thin oxide gate switched by a data signal, the thin oxide gate configured to output a switching signal. The embodiment also includes a thick oxide current source configured to generate a bias current and a modulation current at a laser operating voltage, the modulation current based upon the switching signal, the thick oxide current source further configured to provide the bias current to the laser. The laser is configured to operate at the laser operating voltage based upon the modulation current and the bias current.

Abstract: Disclosed in various embodiments are a circuit and method for driving a signal. In one embodiment, the circuit includes a passive impedance conversion network and at least two signal drivers coupled to the passive impedance conversion network. Each of the signal drivers includes a signal input coupled to a common signal input node.

Abstract: There is provided an echo cancellation method that comprises computing a Discrete Cosine Transform (DCT) domain over a plurality of samples of a first signal to generate a plurality of first DCT samples, selecting one or more first coefficients from the plurality of first DCT samples, computing a DCT domain over a plurality of samples of a second signal to generate a plurality of second DCT samples, selecting one or more second coefficients from the plurality of second DCT samples, wherein the one or more second coefficients are same coefficients as the one or more first coefficients, applying normalized cross correlation to the one or more first coefficients and the one or more second coefficients to generate normalized cross correlation values, cancelling an echo of the second signal from the first signal by determining a bulk delay and a double talk condition based on the normalized cross correlation values.

Abstract: An optic signal transmit system and biasing method and apparatus and system is disclosed to reduce power consumption during non-transmit periods. An optic signal generator receives a bias signal and an outgoing signal. A burst/transmit enable signal enables the transmit system into transmit mode, such as during a transmit window in a time multiplexed environment such as PON networks. A bias circuit biases the driver and/or optic signal generator. To realize power savings, the bias circuit includes one or more stages which are selectively enabled to adequately bias the driver and optic signal generator during transmit windows but disabled during periods when the system is not transmitting. The bias circuit may comprise a current mirror with a reference device, a fixed device, and switched device, which is selectively included in the circuit by a bias switch. The bias switch is responsive to a burst/transmit enable signal or a signal related thereto.

Abstract: Various systems and methods for automatic data rate detection are provided. In one embodiment, a system is provided that includes a clock and data recovery circuit embodied in a first integrated circuit, the clock and data recovery circuit being configured to re-clock a data stream. The system also includes an automatic rate detection system embodied in a second integrated circuit, where the first integrated circuit is in data communication with the second integrated circuit. Also, the automatic rate detection system is configured to determine a data rate of the data stream upon identifying a transition in the data rate of the data stream based upon the state of the at least one status flag received from the clock and data recovery circuit.

Abstract: There is provided a voltage mode push-pull driver output stage with low power consumption and improved output return loss (ORL) suitable for various high bandwidth data transmission applications. By structuring the output stage to have tunable resistances adjustable by voltages applied to transistors, the output stage is readily adaptable to different applications requiring different resistances or impedance matching.

Abstract: There are provided systems and methods for cable detection, such as a video cable. There is provided a device including an output stage, a comparator, a reference selector, a peak detector, and logic gates, which may be arranged to optimize power consumption of the output stage while the cable is unplugged. A method is also provided for such a device, the method comprising detecting whether the cable is unplugged using a cable detector after a first duration of time, turning off the output stage for a second duration of time in response to the cable detector detecting the cable is unplugged, turning on the output stage after the second duration of time, and proceeding to transmit data if the cable detector detects the cable is plugged in for a third period of time, or otherwise repeating the detection, turning off, and turning on steps.

Abstract: Disclosed are various systems and methods for controlling a voice activity detector. In one example approach, a method is provided in which a voice over internet protocol (VOIP) session is initiated in a first gateway with a second gateway. A plurality of jitter adaptation packets are transmitted from the first gateway to the second gateway. Also, the voice activity detector is disabled in the first gateway during the transmission of the jitter adaptation packets. The voice activity detector is enabled in the first gateway after the transmission of the jitter adaptation packets.

Abstract: There is provided a speech encoder for performing an algorithm that comprises obtaining (205) a plurality of open-loop pitch candidates from a current frame of a speech signal, the plurality of open-loop pitch candidates including a first open-loop pitch candidate and a second open-loop pitch candidate; obtaining (205) a voicing information from one or more previous frames; and selecting (280) one of the plurality of open-loop pitch candidates as a final pitch of the current frame using the voicing information from the one or more previous frames. In one aspect, the voicing information from the one or more previous frames includes a previous pitch of the one or more previous frames. In a further aspect, selecting the final pitch of the current frame includes selecting (210) an initial open-loop pitch from that has the maximum long-term correlation value.

Abstract: A signal identification method comprises receiving an incoming signal having incoming frames; receiving an outgoing signal having outgoing frames; extracting outgoing features from a current frame of the outgoing frames; extracting incoming features from a first previous frame of the incoming frames; calculating first feature distances based on corresponding outgoing features and incoming features; deriving a first score based on the first feature distances; extracting incoming features from a second previous frame of the incoming frames; calculating second feature distances based on corresponding outgoing features and incoming features from the second previous frame; deriving a second score based on the second feature distances; and determining whether the outgoing signal includes the incoming signal based on the first score and the second score.

Abstract: There are provided methods and systems for automated testing of echo cancellers using natural speech excitations and evaluating an echo canceller by transmitting a first signal to the echo canceller, wherein the first signal includes a first speech signal and a first marker signal, and wherein the first marker signal is transmitted a first period of time after the first speech signal is transmitted; receiving a second signal from the echo canceller, wherein the second signal includes a second speech signal and a second marker signal; aligning the first speech signal and the second speech signal using the first marker signal and the second marker signal; determining a choppiness of the second speech signal, when a non-linear processor of the echo canceller is on; and determining an audible echo, when a non-linear processor of the echo canceller is off.

Abstract: An electrostatic discharge (ESD) protection circuit includes an NPN transistor having a collector terminal connected to a voltage source and an emitter terminal connected to the ground via a diode. The NPN transistor includes a base terminal for receiving a base current to turn on the NPN transistor to allow an electrostatic discharge at the voltage source to flow through the NPN transistor to the ground. The ESD protection circuit further includes a PMOS transistor having a source terminal coupled to the voltage source and a drain terminal coupled to the base terminal of the NPN transistor. The PMOS transistor includes a gate terminal for receiving a first and a second gate voltage. The ESD protection circuit further includes an R-C circuit coupled between the source voltage and the ground.

Abstract: A density measurement system for measuring a density of a speech processing device including a plurality of channels each having an encoder and a decoder, where each one of the plurality of channels is coupled to another one of the plurality of channels to provide a plurality of coupled pairs. The system comprises a first signal injector module for injecting a first speech signal into a first one of each coupled pair; a second signal injector module for injecting a second speech signal into a second one of each coupled pair; a quality module connected to each decoder for measuring a quality value for each decoder; and an error module connected to each encoder for determining an error value for each encoder, wherein the system determines the density of the speech processing device based on the quality value of each decoder and the error value of each encoder.

Abstract: There is provided a highly distributed multi-core system with an adaptive scheduler. By resolving data dependencies in a given list of parallel tasks and selecting a subset of tasks to execute based on provided software priorities, applications can be executed in a highly distributed manner across several types of slave processing cores. Moreover, by overriding provided priorities as necessary to adapt to hardware or other system requirements, the task scheduler may provide for low-level hardware optimizations that enable the timely completion of time-sensitive workloads, which may be of particular interest for real-time applications. Through this modularization of software development and hardware optimization, the conventional demand on application programmers to micromanage multi-core processing for optimal performance is thus avoided, thereby streamlining development and providing a higher quality end product.

Abstract: Various systems and methods are provided to achieve laser power control. In one embodiment, a system is provided that comprises a counter that holds a digital value. An digital-to-analog converter is employed to convert the digital value to an analog current. A data threshold current is generated by a laser driver based upon the analog current. The data threshold current is employed to represent a data value in a data signal employed to drive a laser diode. Also, circuitry is employed to adjust the digital value based upon a comparison between a target threshold current and a feedback current generated from a laser output of the laser diode.

Abstract: An optic module is disclosed having a shared bus interface, a transmit disable line, a memory and control logic or a processor configured to facilitate address modification via a bus shared by multiple optic modules. A single housing may contain multiple modules, all of which are preferably accessible via a shared host via a shared bus. Standard compliant modules share a common address, which inhibits communication with only a particular optic module, via the shared bus, in a housing containing multiple optic modules. Using a common message to all modules to treat a transmit disable line as a module select line, a single module may be active during an address re-write operation. This process may repeat until all the modules within the housing have unique addresses.

Abstract: A method of adjusting an echo canceller comprises obtaining a first cross-correlation between a far-end signal and an error signal, wherein the error signal is generated by subtracting an output signal of an adaptive filter from a local-end signal; determining whether the first cross-correlation is above a pre-determined threshold; relocating the adaptive filter by a few samples if the determining determines that the first cross-correlation is above a pre-determined threshold; calculating a first improvement indicator parameter, wherein the first improvement indicator parameter is calculated after the relocating the adaptive filter by the few samples; determining whether the first improvement indicator parameter indicates a performance improvement by the adaptive filter after the relocating the adaptive filter by the few samples; calculating a gain based on the local-end signal and the error signal if the determining does not determine the performance improvement; and multiplying the adaptive filter by the ga

Abstract: A method of masking a residual echo signal by an echo canceller is provided. The method comprises receiving a far-end signal, adjusting filter coefficients of an adaptive filter in response to the far-end signal, generating an echo model signal based on the far-end signal using the adaptive filter, receiving a near-end signal, subtracting the echo model signal from the near-end signal to generate an output signal, defining a spectral mask based on the near-end signal, wherein the spectral mask is indicative of near-end spectral peaks and near-end spectral valleys, de-emphasizing the output signal in spectral regions of the near-end spectral peaks, and emphasizing the output signal in spectral regions of the near-end spectral valleys, wherein the de-emphasizing occurs during filter coefficients determination for the adaptive filter. A weighted filter may perform the de-emphasizing and the emphasizing operations, where the weighted filter uses medium term spectral characteristics of the near-end signal.