Victor L Demjanenko, 664420 Beach Ridge Rd, Lockport, NY 14094

6633604, Oct 14, 2003

Aug 11, 1998

09/132600

Victor Demjanenko - Pendleton NY
Frederic J. Hirzel - Clinton Township MI

Vocal Technologies, Ltd. - Buffalo NY

H04B 138

375222, 375242

A method of discovering characteristics of a PCM channel between a first PCM modem and a second PCM modem, comprising the steps of creating a PCM representation of a probing tone ensemble, where the probing tone ensemble comprises one or more tones, transmitting the PCM representation of the probing tone ensemble from the first PCM modem to the second PCM modem, receiving the PCM representation of the probing tone ensemble by the second PCM modem; and, processing the PCM representation of the probing tone ensemble to determine characteristics of the PCM channel. The invention also comprises a method of improving echo canceller training of a modem comprising generating an echo canceller training reference signal modifying the echo canceller training reference signal sending the modified echo canceller training reference signal into a channel, receiving an echo of the modified echo canceller training signal; and, processing the echo canceller training reference signal and the received echo of the modified echo canceller training reference signal.

6643270, Nov 4, 2003

Apr 8, 1998

09/057292

Victor Demjanenko - Pendleton NY
Frederic J. Hirzel - Sunnyvale CA

Vocal Technologies, Ltd - Buffalo NY

H04B 1404

370282, 370523, 375222, 375242

Methods of determining systemic impairments in a telecommunications network comprise sending a candidate set of digital symbols from a digital modem to an analog modem. The symbols are affected by systemic impairments in the network. Data information symbols or mapping tables are derived in the analog modem. The data information symbols or mapping tables are then provided to the digital modem. The digital modem may use the data information symbols or mapping tables in a variety of manners, such as for data transmission, spectral shaping, echo cancellation, or adaptation to robbed bit signaling.

6848073, Jan 25, 2005

Oct 8, 2001

09/973483

Frederic J. Hirzel - Sunnyvale CA, US
Victor Demjanenko - Pendleton NY, US

Vocal Technologies, Ltd. - Buffalo NY

H03M 1303

714786, 714755, 714792, 375265

A method of applying a multidimensional error reduction/correction algorithm on a stream of one dimensional symbols, by converting the stream of one dimensional symbols into a corresponding stream of two dimensional symbols; and, applying the multidimensional error reduction/correction algorithm to the stream of two dimensional symbols. The invention also provides a method of normalizing a metric used by an error reduction/correction algorithm on a stream of symbols wherein the symbols are non-uniformly spaced, by: determining a minimum distance (dmin) between two closest symbols in the stream, for each symbol in the stream, determining a minimum distance (dsym) between each symbol in the stream and each of its adjacent neighboring symbols, and, normalizing the metric used by the error reduction/correction algorithm by the ratio dmin/dsym.

2002003, Mar 21, 2002

Jul 27, 2001

09/916865

Victor Demjanenko - Pendleton NY, US
Frederic Hirzel - Clinton Township MI, US
Juan Torres - Orchard Park NY, US

H04L027/06

375/341000

In a receiver, an outer decoder in an inner/outer decoder scheme receives bit error information or bit error probability information from an inner decoder rather than being generated internally by the outer decoder. The inner decoder may be a soft-decision decoder that provides bit error probabilities, or a sum-product decoder that provides bit error information. Thus, unlike conventional outer decoders, the outer decoder does not require a conventional first stage for determining errors in the output bit stream of the inner decoder based on the bits of the output bit stream themselves. A related transmitter uses a sum-product inner decoder in conjunction with an outer decoder.

2002005, May 2, 2002

Apr 30, 2001

09/846061

Victor Demjanenko - Pendleton NY, US
Frederic Hirzel - Clinton Township MI, US
Juan Torres - Orchard Park NY, US

H04L027/36
H03D001/00
H04L027/06

375/298000, 375/340000

A transmitter produces a modulated signal with forward error correction from an information bit stream in a QAM transmitter. The transmitter produces parity bit streams that correspond to an inputted information bit stream using first and second concatenated coders interconnected by an interleaver. Subsets of the first and second parity bit streams are selected in accordance with a puncturing pattern. A variety of novel puncturing patterns providing various coding rates for various constellations are disclosed. The transmitter combines the selected subsets of said first and second parity bit streams with said information bit stream. A QAM symbol stream is produced by mapping a first subset of the combined bit streams to an I dimension and mapping a second subset of the combined bit streams to a Q dimension. The QAM symbol stream is modulated to produce a modulated signal that is transmitted over a communication link. A complementary receiver is also disclosed. The puncturing pattern used in the transmitter may be adapted based on a performance metric determined in the receiver.

2002013, Sep 19, 2002

Nov 13, 2001

09/991372

Victor Demjanenko - Pendleton NY, US
Frederic Hirzel - Clinton Township MI, US
Juan Torres - Orchard Park NY, US

H04L027/36
H04L023/02
H04L005/12

375/298000, 375/261000

A non-separable symbol constellation may comprise constituent constellations having separable I and Q. Such a non-separable constellation may be decoded with the efficiency of a separable constellation by decoding for each of the constituent constellations individually. In a transmitter, transmit data may be mapped to symbols by selecting a constituent constellation and I and Q values for a symbol to be transmitted. In a receiver, decoders may decode for each constituent individually.

2002015, Oct 17, 2002

Feb 19, 2002

10/079202

Victor Demjanenko - Pendleton NY, US
Juan Torres - Orchard Park NY, US

H04L027/00

375/259000

The encoder of a communication device is configurable such that the encoder may operate in any of a variety of forward error correction modes. Further, for each mode, a variety of encoding parameters may be configured. The configurability of forward error correction modes and/or parameters enables communication devices to perform interactive configuration processes, whereby a communicating device specifies the type of forward error correction that the other is to perform. This configuration may be bidirectional, such that each device selects the forward error correction provided by the other. Each device may further configure its decoder to decode the forward error correction mode that it has selected for the other communication device. In other embodiments two communicating devices may implement two different modes of forward error correction.

2003012, Jul 10, 2003

Nov 8, 2002

10/290662

Victor Demjanenko - Pendleton NY, US
Frederic Hirzel - Clinton Township MI, US

H04B014/04

375/222000, 375/242000

A method of determining digital channel attenuation; comprising the steps of: receiving a known training sequence of PCM codes, which PCM codes are subjected to the attenuation within the digital channel; quantizing the received known training sequence of PCM codes according to a predetermined thresholding procedure; identifying identical PCM codes created as a result of the thresholding procedure; and, determining the attenuation of the digital channel based upon the identification of identical PCM codes. A method is also disclosed for determining a digital channel PCM code transformation comprising receiving a known training sequence of PCM codes, which PCM codes are subjected to the PCM code transformation within the digital channel, quantizing the received known training sequence of PCM codes according to a predetermined thresholding procedure, and determining the transformation of transmitted codes to those received. A method is also disclosed for improved echo cancellation in a communications network having an analog and a digital modem, comprising saving codes transmitted from the digital modem to the analog modem for echo cancellation, transforming, by a mapping table, codes transmitted from said digital modem to codes received by the analog modem, and, using the received codes as a reference signal for cancellation of echo. A method of improved spectral shaping using a transmit shaping transfer function in a communications network having an analog and a digital modem, comprising, transforming, by a mapping table, codes transmitted from the digital modem to codes received by the analog modem, using the received codes for transformation to their linear value equivalent representations, and, applying the linear value representations to the transmit shaping transfer function.