Christopher M Riddle

US Patent:

6389067, May 14, 2002

Filed:

Jun 10, 1999

Appl. No.:

09/329777

Inventors:

Christopher C. Riddle - San Diego CA
Jeffrey A. Levin - San Diego CA

Assignee:

Qualcomm, Inc. - San Diego CA

International Classification:

H04B 1700

US Classification:

375225, 375150

Abstract:

A Wireless Code Division Multiple Access method and apparatus for determining the transmitted rate of a voice/data signal from a mobile station to a Base Station. Variable rate vocoders transmit voice at one of several predetermined frame rates. The receiver determines the transmitted rate based on one of several frame parameters. One of the parameters is received frame energy. The received frame energy is measured over the length of the relevant portion of the frame. Energy is measured over the half of the frame that can only contain energy if a full rate frame is sent. If the energy measured exceeds a threshold, then full rate is indicated. Else, energy is measured over the fourth of a frame that can only contain energy if a half rate frame is sent. If the energy exceeds a threshold, then half rate is indicated. The procedure is repeated for quarter and eighth rates.

US Patent:

6483817, Nov 19, 2002

Filed:

Oct 14, 1998

Appl. No.:

09/172332

Inventors:

Franklin Antonio - Del Mar CA
Christopher C. Riddle - San Diego CA

Assignee:

Qualcomm Incorporated - San Diego CA

International Classification:

H04J 100

US Classification:

370328, 370335, 370342, 370537

Abstract:

A base station architecture splits modem functionality into modulator and demodulator entities, each configured to handle multiple telephone calls. A high-speed digital bus with associated routing elements connects multiple-channel (i. e. , multiuser) modulator and demodulator elements. The modulator and demodulator elements may be physically separated, residing on different cards, and even different shelves, within the base station. On each modulator card, the outputs of multiple modulators may be combined by digitally upconverting the output of each modulator by a different amount and summing the results.

US Patent:

6600792, Jul 29, 2003

Filed:

Jun 26, 1998

Appl. No.:

09/105532

Inventors:

Franklin P. Antonio - Del Mar CA
Walid Hamdy - San Diego CA
Nitin Kasturi - Los Gatos CA
Christopher C. Riddle - San Diego CA
David P. Oses - San Diego CA

Assignee:

Qualcomm Incorporated - San Diego CA

International Classification:

H04L 2549

US Classification:

375297, 330149, 455126

Abstract:

A predistortion technique for high power amplifiers includes an adaptive predistortion algorithm that operates independently of data samples to write a set of complex gain values, or predistortion parameters, to a lookup table. The algorithm may be processor-driven. The gain values are taken from the lookup table and multiplied by a complex digital baseband waveform. The gain values may first be subjected to interpolation. The downconverted output of the amplifier is measured to gauge the efficacy of the predistortion. Based on the effect of the predistortion upon the ratio of in-band power to out-of-band power, decisions are made on the set of predistortion parameters for the next iteration of the algorithm. The algorithm runs continuously, perturbing parameters and adapting the predistortion functions accordingly in an effort to continually reflect instantaneous amplitude-modulation and phase-modulation relationships that may change over time with temperature variation or component aging.

US Patent:

6650187, Nov 18, 2003

Filed:

Aug 29, 2002

Appl. No.:

10/233246

Inventors:

Christopher Riddle - San Diego CA
Serguei A. Glazko - San Diego CA

Assignee:

Qualcomm, Incorporated - San Diego CA

International Classification:

H03L 700

US Classification:

331 17

Abstract:

A phase lock loop apparatus and method is disclosed. A typical apparatus includes a demodulator receiving a phase error signal from a comparator at a chip rate and providing a phase error update over a symbol period from the phase error signal wherein the chip rate is higher than the symbol rate. A phase discriminator produces a phase error output at the symbol rate from the phase error update based upon a signal modulation type. A loop filter produces one or more phase estimate parameters at a symbol rate from the phase error output and a numerically controlled oscillator (NCO) extrapolates a phase reference at a chip rate from the one or more phase estimate parameters at a symbol rate. The comparator produces the phase error signal to the demodulator based upon the phase reference and an incoming signal.

US Patent:

6650873, Nov 18, 2003

Filed:

Mar 16, 2001

Appl. No.:

09/809836

Inventors:

Jiangxin Chen - San Diego CA
Christopher Riddle - San Diego CA
Serguei Glazko - San Diego CA

Assignee:

Qualcomm, Incorporated - San Diego CA

International Classification:

H04Q 720

US Classification:

455 69, 455458, 455574, 455522, 370335, 370329

Abstract:

A wireless communication device performance, such as standby time, is improved by adaptively allocating surplus system resources to change quick paging channel parameters at the system, such a system being for example, a base station. Adaptively adjusting the quick paging channel parameters allows available base station resources to be allocated to the quick paging channel, thereby enabling the wireless communication device to demodulate the quick paging channel more reliably. Parameters such as the number of quick paging channels, the data rate used by the paging channel, and the quick paging channel transmit power level are weighed and adjusted.

US Patent:

6999533, Feb 14, 2006

Filed:

Nov 30, 2001

Appl. No.:

10/000817

Inventors:

Chandra R. Murthy - San Jose CA, US
Serguei A. Glazko - San Diego CA, US
Christopher C. Riddle - San Diego CA, US
Angelica Wong - San Francisco CA, US

Assignee:

QUALCOMM, Incorporated - San Diego CA

International Classification:

H04L 27/06

US Classification:

375343

Abstract:

The invention provides the ability to exploit redundancy characteristics of an equation set used to generate waveforms for wireless communication. In doing so, the invention can reduce the number of correlation values that need to be calculated in order to determine the most likely transmitted code word. In particular, the invention can exploit the redundancy characteristics of the equation set in a novel and unique fashion by separating the vector and calculating partial correlations for each separated portion of the vector. The techniques can drastically reduce the number of correlation values that need to be computed for demodulation, and can also reduce the total number of computations. In this manner, the demodulator of a wireless communication device can be simplified without negatively impacting performance.

US Patent:

7181244, Feb 20, 2007

Filed:

Nov 15, 2001

Appl. No.:

09/998860

Inventors:

Bruce A. Judson - San Luis Obispo CA, US
Christopher C. Riddle - San Diego CA, US

Assignee:

Qualcomm, Incorporated - San Diego CA

International Classification:

H04M 1/00

US Classification:

4555621, 4554561, 455524

Abstract:

A novel mobile unit which communicates with a new and advantageous base station. The mobile unit includes a system for generation of position information and a transceiver for transmitting the position information. In the preferred embodiment, the transceiver is a CDMA system and the system for generating position information includes an arrangement for receiving a GPS signal. In the preferred embodiment, a GPS assisted arrangement is employed which is adapted to receive a signal from an airborne platform as well as from a satellite based platform. The inventive base station is adapted to receive position information from a remote unit and provide a received position signal in response thereto. The novel base station is further equipped with a mechanism for directing a beam in response to the received position signal. In the illustrative embodiment, the mechanism for directing the beam is a smart antenna system including an antenna array and a beamforming network for driving the array to output the directed beam.

US Patent:

7340268, Mar 4, 2008

Filed:

Jun 10, 2003

Appl. No.:

10/457846

Inventors:

Hyukjun Oh - Santa Clara CA, US
Nitin Kasturi - Los Gatos CA, US
Messay Amerga - San Diego CA, US
Chih-Ping Hsu - San Diego CA, US
Christopher C. Riddle - San Diego CA, US
Andrew Sendonaris - San Jose CA, US

Assignee:

QUALCOMM Incorporated - San Diego CA

International Classification:

H04B 7/00
H04Q 7/20

US Classification:

455522, 455 69, 455 6711, 455442, 370320, 370332, 370335, 370345

Abstract:

The reliability of transmit power control (TPC) commands received from a transmitter is determined based on a TPC target value. The TPC target value is derived based on a TPC threshold and possibly a weight, depending on the receiver implementation. A received TPC command is considered reliable if its absolute value exceeds the TPC target value. Received TPC commands deemed as unreliable are discarded and not used for power control. Multiple TPC target values, used for detecting UP and DOWN commands, may be derived with multiple scaling factors. For a receiver in soft handover and receiving TPC commands from multiple transmitters, a different TPC target value may be derived for each transmitter. The received TPC commands for each transmitter are compared against that transmitter's TPC target value. Received TPC commands deemed as unreliable are discarded and not combined.