Abstract: An optical resonant modulator based on coupling modulation, comprising a resonant structure with an embedded Mach-Zehnder interferometer that is differentially driven to induced amplitude modulation at the output port. The principle of coupling modulation enables high data/baud rates to be achieved in a photonic integrated circuit, e.g. silicon, footprint that is considerably smaller than that of a conventional traveling-wave Mach-Zehnder modulator, in particular by utilizing space saving features, such as ring resonator phase shifters and bend waveguide arms.

Abstract: An optical resonant modulator based on coupling modulation, comprising a resonant structure with an embedded Mach-Zehnder interferometer that is differentially driven to induced amplitude modulation at the output port. The principle of coupling modulation enables high data/baud rates to be achieved in a photonic integrated circuit, e.g. silicon, footprint that is considerably smaller than that of a conventional traveling-wave Mach-Zehnder modulator, in particular by utilizing space saving features, such as ring resonator phase shifters and bend waveguide arms.

Abstract: Method and apparatus of an optical routing system (“ORS”) capable of automatically discovering intra-nodal fiber connections using a test channel transceiver (“TCT”) are disclosed. ORS, in one embodiment, includes a set of reconfigurable optical add-drop multiplexer (“ROADM”) modules, intra-nodal fiber connections, add-drop modules, and a test module. The ROADM modules are able to transmit or receive optical signals via optical fibers. The intra-nodal fiber connections are configured to provide optical connections. The add-drop modules are able to selectively make connections between input ports and output ports. The test module containing TCT is configured to identify at least a portion of intra-nodal connections of the ROADM via a test signal operating with a unique optical frequency.

Abstract: Method and apparatus of an optical routing system (“ORS”) capable of automatically discovering intra-nodal fiber connections using a test channel transceiver (“TCT”) are disclosed. ORS, in one embodiment, includes a set of reconfigurable optical add-drop multiplexer (“ROADM”) modules, intra-nodal fiber connections, add-drop modules, and a test module. The ROADM modules are able to transmit or receive optical signals via optical fibers. The intra-nodal fiber connections are configured to provide optical connections. The add-drop modules are able to selectively make connections between input ports and output ports. The test module containing TCT is configured to identify at least a portion of intra-nodal connections of the ROADM via a test signal operating with a unique optical frequency.

Abstract: Method and apparatus of an optical routing system (“ORS”) capable of automatically discovering intra-nodal fiber connections using a test channel transceiver (“TCT”) are disclosed. ORS, in one embodiment, includes a set of reconfigurable optical add-drop multiplexer (“ROADM”) modules, intra-nodal fiber connections, add-drop modules, and a test module. The ROADM modules are able to transmit or receive optical signals via optical fibers. The intra-nodal fiber connections are configured to provide optical connections. The add-drop modules are able to selectively make connections between input ports and output ports. The test module containing TCT is configured to identify at least a portion of intra-nodal connections of the ROADM via a test signal operating with a unique optical frequency.

Abstract: Method and apparatus of an optical routing system (“ORS”) capable of automatically discovering intra-nodal fiber connections using a test channel transceiver (“TCT”) are disclosed. ORS, in one embodiment, includes a set of reconfigurable optical add-drop multiplexer (“ROADM”) modules, intra-nodal fiber connections, add-drop modules, and a test module. The ROADM modules are able to transmit or receive optical signals via optical fibers. The intra-nodal fiber connections are configured to provide optical connections. The add-drop modules are able to selectively make connections between input ports and output ports. The test module containing TCT is configured to identify at least a portion of intra-nodal connections of the ROADM via a test signal operating with a unique optical frequency.

Abstract: Adaptive Gain Control (AGC) is performed directly in a coded domain. A Coded Domain Adaptive Gain Control (CD-AGC) system modifies at least one parameter of a first encoded signal, resulting in corresponding modified parameter(s). The CD-VQE system replaces the parameter(s) of the first encoded signal with the modified parameter(s), resulting in a second encoded signal. In a decoded state, the second encoded signal approximates a target signal that is a function of two signals, including the first encoded signal and a third encoded signal, in at least a partially decoded states. Thus, the first encoded signal does not have to go through intermediate decode/re-encode processes, which can degrade overall speech quality. Computational resources required for a complete re-encoding are not needed. Overall delay of the system is minimized. The CD-AGC system can be used in any network in which signals are communicated in a coded domain, such as a Third Generation (3G) wireless network.

Abstract: A system, apparatus, method, and computer-readable medium for coded-domain echo cancellation. The method includes receiving a signal including at least one packet, and replacing the at least one packet with a replacement packet. In one example, the replacement packet is a comfort noise packet (such as a SID_UPDATE packet) or a NO_DATA packet. In an example embodiment, the at least one packet included in the signal includes one or more comfort noise packets, and, prior to the replacing, the one or more comfort noise packet(s) are stored in a buffer. In another example, prior to the replacing, the at least one packet is compared to a reference packet to determine whether the at least one packet is an echo packet. The packet, in one example, is encoded based on an adaptive multi-rate (AMR) (e.g., AMR-NB or AMR-WB) codec.

Abstract: A method and corresponding apparatus for coded-domain acoustic echo control is presented. An echo control problem is considered as that of perceptually matching an echo signal to a reference signal. A perceptual similarity function that is based on the coded spectral parameters produced by the speech codec is defined. Since codecs introduce a significant degree of non-linearity into the echo signal, the similarity function is designed to be robust against such effects. The similarity function is incorporated into a coded-domain echo control system that also includes spectrally-matched noise injection for replacing echo frames with comfort noise. Using actual echoes recorded over a commercial mobile network, it is shown herein that the similarity function is robust against both codec non-linearities and additive noise. Experimental results further show that the echo-control is effective at suppressing echoes compared to a Normalized Least Mean Squared (NLMS)-based echo cancellation system.

Abstract: A method and corresponding apparatus for coded-domain acoustic echo control is presented. An echo control problem is considered as that of perceptually matching an echo signal to a reference signal. A perceptual similarity function that is based on the coded spectral parameters produced by the speech codec is defined. Since codecs introduce a significant degree of non-linearity into the echo signal, the similarity function is designed to be robust against such effects. The similarity function is incorporated into a coded-domain echo control system that also includes spectrally-matched noise injection for replacing echo frames with comfort noise. Using actual echoes recorded over a commercial mobile network, it is shown herein that the similarity function is robust against both codec non-linearities and additive noise. Experimental results further show that the echo-control is effective at suppressing echoes compared to a Normalized Least Mean Squared (NLMS)-based echo cancellation system.

Abstract: A method and corresponding apparatus for coded-domain acoustic echo control is presented. An echo control problem is considered as that of perceptually matching an echo signal to a reference signal. A perceptual similarity function that is based on the coded spectral parameters produced by the speech codec is defined. Since codecs introduce a significant degree of non-linearity into the echo signal, the similarity function is designed to be robust against such effects. The similarity function is incorporated into a coded-domain echo control system that also includes spectrally-matched noise injection for replacing echo frames with comfort noise. Using actual echoes recorded over a commercial mobile network, it is shown herein that the similarity function is robust against both codec non-linearities and additive noise. Experimental results further show that the echo-control is effective at suppressing echoes compared to a Normalized Least Mean Squared (NLMS)-based echo cancellation system.

Abstract: In some communications systems, unsynchronized near-end and far-end packets of communications signals can reduce or impair performance of processing of packets, such as to the case of Coded Domain Media Quality Enhancement. Therefore, a system may synchronize the incoming signals to enhance quality. A relative delay determination module according to an example embodiment of this invention determines a synchronization and relative delay between packets belonging to different packet streams arriving at a network node in a packet-based network by computing a time synchronization parameter based on a time reference of timestamps of the signals and reports the relative delay to a module making use of the relative delay such as a voice quality enhancement or an echo control module. By synchronizing the packets at the location within the network, source clocks at end or edge nodes of the network can operate with reduced synchronization, simplifying network operations and management thereof.

Abstract: Media processing of real-time protocol (RTP) packets used in Voice over Internet Protocol (VoIP) and other time sensitive applications makes efficient use of network resources, e.g., by dropping or changing the size of certain packets, but hinders measuring and reporting end-to-end reception quality. Because media processing changes RTP packets between a sender and receiver, causing a difference between what is sent and received, end-to-end reception quality cannot be measured validly without accounting for these changes.

Abstract: Media processing of real-time protocol (RTP) packets used in time sensitive applications makes efficient use of network resources, e.g., by dropping or resizing the packets, but hinders measuring and reporting end-to-end reception quality. Because media processing causes a difference between what is sent and received, end-to-end reception quality cannot be measured validly without accounting for this difference. Accordingly, a method and corresponding apparatus are provided to track changes to RTP packets of an RTP session caused by media processing, modify RTP packet information of the RTP packets based on the tracked changes, correct RTP control protocol (RTCP) packets corresponding to the RTP session based on the tracked changes, the corrected RTCP packets being a measure of the end-to-end reception quality of the RTP session, and report the end-to-end reception quality of the RTP session by forwarding the corrected RTCP packets. Thus, end-to-end reception quality can be validly measured and reported.

Abstract: A method and corresponding apparatus for coded-domain acoustic echo control is presented. An echo control problem is considered as that of perceptually matching an echo signal to a reference signal. A perceptual similarity function that is based on the coded spectral parameters produced by the speech codec is defined. Since codecs introduce a significant degree of non-linearity into the echo signal, the similarity function is designed to be robust against such effects. The similarity function is incorporated into a coded-domain echo control system that also includes spectrally-matched noise injection for replacing echo frames with comfort noise. Using actual echoes recorded over a commercial mobile network, it is shown herein that the similarity function is robust against both codec non-linearities and additive noise. Experimental results further show that the echo-control is effective at suppressing echoes compared to a Normalized Least Mean Squared (NLMS)-based echo cancellation system.

Abstract: A method, apparatus, system, and program, for evaluating communication signals exchanged between communicating devices through at least one communication path. The method comprises performing a similarity function or distance function to determine if the communication signals include at least one substantially similar pattern, and reporting an existence of a predetermined condition if it is determined in the performing that the communication signals include a substantially similar pattern. The predetermined condition can be, for example, an echo condition in a single talk or double talk condition, and the echo condition can be acoustical or electrical in origin. The method adapts features and techniques that have been used successfully in speech recognition for successful application in the echo detection and double talk contexts, and the similarity function preferably is based on cepstral correlation according to the invention.

Abstract: A method, apparatus, system, and program, for evaluating a call communicated between communicating devices through at least one communication path. The method comprises segmenting, into first segments, at least one first communication signal traveling from a first one of the communicating devices to a second one of the communicating devices through the at least one communication path, and segmenting, into second segments, at least one second communication signal traveling from the second one of the communicating devices to the first one of the communicating devices through the at least one communication path. The method also comprises determining predetermined call characteristics based on the first and second segments, and identifying whether an echo is present in the call based on a result of the determining.

Abstract: Background noise, optionally spectrally matched, is performed directly in a coded domain. A Coded Domain Spectrally Matched Noise Injection (CD-SMNI) system modifies at least one parameter of a first encoded signal, resulting in corresponding modified parameter(s). The CD-SMNI system replaces the parameter(s) of the first encoded signal with the modified parameter(s), resulting in a second encoded signal. In a decoded state, the second encoded signal approximates background noise in the first encoded signal in a decoded state. Thus, the first encoded signal does not have to go through intermediate decode/re-encode processes, which can degrade overall speech quality. Computational resources required for a complete re-encoding are not needed. Overall delay of the system is minimized. The CD-SMNI system can be used in any network in which signals are communicated in a coded domain, such as a Third Generation (3G) wireless network using Enhanced Variable Rate Coders (EVRCs).

Abstract: Adaptive Gain Control (AGC) is performed directly in a coded domain. A Coded Domain Adaptive Gain Control (CD-AGC) system modifies at least one parameter of a first encoded signal, resulting in corresponding modified parameter(s). The CD-VQE system replaces the parameter(s) of the first encoded signal with the modified parameter(s), resulting in a second encoded signal. In a decoded state, the second encoded signal approximates a target signal that is a function of two signals, including the first encoded signal and a third encoded signal, in at least a partially decoded states. Thus, the first encoded signal does not have to go through intermediate decode/re-encode processes, which can degrade overall speech quality. Computational resources required for a complete re-encoding are not needed. Overall delay of the system is minimized. The CD-AGC system can be used in any network in which signals are communicated in a coded domain, such as a Third Generation (3G) wireless network.

Abstract: Background noise, optionally spectrally matched, is performed directly in a coded domain. A Coded Domain Spectrally Matched Noise Injection (CD-SMNI) system modifies at least one parameter of a first encoded signal, resulting in corresponding modified parameter(s). The CD-SMNI system replaces the parameter(s) of the first encoded signal with the modified parameter(s), resulting in a second encoded signal. In a decoded state, the second encoded signal approximates background noise in the first encoded signal in a decoded state. Thus, the first encoded signal does not have to go through intermediate decode/re-encode processes, which can degrade overall speech quality. Computational resources required for a complete re-encoding are not needed. Overall delay of the system is minimized. The CD-SMNI system can be used in any network in which signals are communicated in a coded domain, such as a Third Generation (3G) wireless network.