Search

Roland Sperlich Phones & Addresses

  • Rockwall, TX
  • 3805 San Jacinto St, Dallas, TX 75204
  • 3809 San Jacinto St, Dallas, TX 75204
  • 1033 Tumlin St NW #C 3, Atlanta, GA 30318
  • 301 10Th St NW, Atlanta, GA 30318
  • 315 Turnpike St, North Andover, MA 01845
  • Andover, MA

Publications

Us Patents

Distortion Compensation In A Communication System

View page
US Patent:
7778345, Aug 17, 2010
Filed:
Nov 7, 2007
Appl. No.:
11/936551
Inventors:
Roland Sperlich - Dallas TX, US
Gregory C. Copeland - Plano TX, US
Assignee:
Texas Instruments Incorporated - Dallas TX
International Classification:
H04B 15/00
H04B 1/10
H04L 25/49
US Classification:
375285, 375296, 375346
Abstract:
In one embodiment of the invention, a modulator mixes a transmit-path signal based on a local oscillator (LO) signal and an amplifier amplifies the mixed transmit-path signal to generate an output signal for transmission. A demodulator generates a receive-path signal based on the output signal and the LO signal. Phase-shift control components provide the output signal and the LO signal to the demodulator during a first time duration and provide a phase-shifted version of one of the output signal and the LO signal to the demodulator during a second time duration. The demodulator generates a second receive-path signal based on the one of the phase-shifted output signal and the phase-shifted LO signal during the second time duration. At least one predistortion circuit adjusts at least one of the transmit-path signal and the receive-path signal based on a difference in signal characteristics of the receive-path signal during the second time duration relative to the first time duration.

Simplified Digital Predistortion In A Time-Domain Duplexed Transceiver

View page
US Patent:
7783263, Aug 24, 2010
Filed:
Dec 14, 2006
Appl. No.:
11/610563
Inventors:
Roland Sperlich - Dallas TX, US
Gregory C. Copeland - Plano TX, US
Assignee:
Texas Instruments Incorporated - Dallas TX
International Classification:
H04B 7/005
H04J 3/00
US Classification:
455 73, 370278, 370280
Abstract:
A transceiver for time-domain duplexed (TDD) communications, for example in connection with wireless broadband data communications, is disclosed. The transceiver includes digital predistortion compensation circuitry, which compensates the digital signals to be transmitted based on feedback signals from the output of the power amplifier, in order to linearize the output from the power amplifier. The feedback signals from the power amplifier are coupled back to the digital predistortion circuitry over part of the same receive path as the received signals from the wireless communications channel. The shared path includes analog-to-digital converters that are used both in the transmit period of the TDD cycle to convert the feedback signals from the power amplifier output, and in the receive period of the TDD cycle to convert the analog received signals.

Active Skew Control Of A Digital Phase-Lock Loop Using Delay Lock-Loops

View page
US Patent:
7814450, Oct 12, 2010
Filed:
Dec 29, 2007
Appl. No.:
11/967079
Inventors:
Roland Sperlich - Dallas TX, US
Amer Hani Atrash - Dallas TX, US
Assignee:
Texas Instruments Incorporated - Dallas TX
International Classification:
G06F 17/50
US Classification:
716 6, 716 1, 716 4, 716 5
Abstract:
Systems and methods for transmitting a signal having a desired phase at the device are disclosed. The systems and methods further include determining a signal path length to a device over a transmission line and adding a delay to a signal to be transmitted over the transmission line. The determination is made in response to determining the path length to the device.

Systems And Methods Of Power Amplifier Digital Pre-Distortion

View page
US Patent:
8306149, Nov 6, 2012
Filed:
Oct 1, 2009
Appl. No.:
12/571435
Inventors:
Fernando Alberto Mujica - Allen TX, US
Hardik Prakash Gandhi - Mountain View CA, US
Lei Ding - Plano TX, US
Milind Borkar - Dallas TX, US
Zigang Yang - Plano TX, US
Roland Sperlich - Dallas TX, US
Lars Morten Jorgensen - Royal Oaks CA, US
William L. Abbott - Portola Valley CA, US
Assignee:
Texas Instruments Incorporated - Dallas TX
International Classification:
H04L 25/03
H04L 25/49
US Classification:
375296, 375297, 4551143, 708316
Abstract:
An apparatus is provided. In the apparatus, an input to index (I2I) module maps a complex input into a real signal. A real data tap delay line is coupled to the I2I module and includes N delay-elements. A complex data tap delay line is configured to receive the complex input and includes M delay elements. A set of K of non-linear function modules is also provided. Each non-linear function module from the set has at least one real input, at least one complex input, and at least one complex output. A configurable connectivity crossbar multiplexer couples K of the N real tap delay line elements to real inputs of the set non-linear functions and couples K of the M complex tap delay line elements to complex inputs of the set non-linear function modules.

System And Method For Estimating A Transmit Channel Response And/Or A Feedback Channel Response Using Frequency Shifting

View page
US Patent:
8306150, Nov 6, 2012
Filed:
Jun 25, 2010
Appl. No.:
12/823714
Inventors:
Fernando A. Mujica - Allen TX, US
Carson A. Wick - Atlanta GA, US
Lei Ding - Plano TX, US
Milind Borkar - Dallas TX, US
Roland Sperlich - Dallas TX, US
Assignee:
Texas Instruments Incorporated - Dallas TX
International Classification:
H04K 1/02
H04L 25/03
H04L 25/49
US Classification:
375296, 375297, 375285, 375231, 375232, 4551142, 4551143
Abstract:
Systems and methods for identifying a transmission channel response and a feedback channel response from a plurality of composite system responses are disclosed. A plurality of shifted feedback signals are created by shifting a feedback signal frequency by a plurality of first offset values and/or by shifting a transmission signal frequency by a plurality of second offset values. The feedback signals are compared to an input signal to identify the transmission channel response and/or a feedback channel response. A control signal is generated for a pre-distortion circuit to modify the input signal by an inverse of the transmission channel response. The composite system response is measured at a plurality of operating frequencies and at the plurality of offset values. The measurements are stored in a matrix and singular value decomposition is applied to the matrix of measurements to calculate the transmission channel response and feedback channel response.

Joint Transmit And Receive I/Q Imbalance Compensation

View page
US Patent:
8311083, Nov 13, 2012
Filed:
Dec 29, 2009
Appl. No.:
12/648898
Inventors:
Lei Ding - Dallas TX, US
Zigang Yang - Plano TX, US
Fernando Mujica - Allen TX, US
Roland Sperlich - Dallas TX, US
Assignee:
Texas Instruments Incorporated - Dallas TX
International Classification:
H04L 5/16
US Classification:
375219, 375260, 375296, 375340, 455 631, 455 6713, 4551142, 455126
Abstract:
Conventional transceivers do provide some compensation for in-phase/quadrature (I/Q) imbalance. However, these techniques do not separately compensate for I/Q imbalance for the transmitter and receiver sides of the transceiver. Here, a transceiver is provided that allows for compensation of I/Q imbalance in the transmitter and receiver irrespective of the other to allow for a more accurate transceiver.

Hybrid Doherty Amplifier System And Method

View page
US Patent:
20080111622, May 15, 2008
Filed:
Nov 14, 2007
Appl. No.:
11/940096
Inventors:
Roland Sperlich - Dallas TX, US
Gregory Clark Copeland - Plano TX, US
Russell Hoppenstein - Richardson TX, US
International Classification:
H03F 3/68
US Classification:
330124 R
Abstract:
One embodiment of the invention includes an amplifier system. The system comprises a digital predistortion (DPD) system configured to receive an input signal and to provide the input signal as a first digital signal component along a first amplifier path and a second digital signal component along a second amplifier path. The system also comprises a first digital-to-analog converter (DAC) configured to convert the first digital signal component to a first analog signal component and a second DAC configured to convert the second digital signal component to a second analog signal component. The system further comprises a Doherty amplifier comprising a main amplifier in the first amplifier path that is configured to amplify the first analog signal component and a peak amplifier in the second amplifier path that is configured to amplify the second analog signal component.

System And Methods For Digitally Correcting A Non-Linear Element Using A Digital Filter For Predistortion

View page
US Patent:
20080130789, Jun 5, 2008
Filed:
Dec 12, 2006
Appl. No.:
11/638300
Inventors:
Gregory Clark Copeland - Plano TX, US
Roland Sperlich - Dallas TX, US
International Classification:
H04L 25/03
US Classification:
375297
Abstract:
System and methods for a digital linearization of a non linear element. Digital predistortion methods and circuitry for linearizing a non-linear element that address long or “memory” effects and shorter duration effects, these two predistortion functions are operated together in an adaptive fashion with the non-linear element to provide a highly linear system. A short duration predistortion block comprises an Nth order polynomial filter coupled to a programmable linear equalizer. The Nth order filter includes programmable non-linearities and variable delay taps. The Nth order filter may be configured to implement a non-sequential or a sequential ordered polynomial. The equalizer may, in a preferred embodiment, include circuitry for equalizing imbalances between real and complex signal values. The Nth order filter may implement a compound Volterra filter. The combined system of the predistortion circuitry and a non-linear element has a linear input-output signal response. Methods for initializing, parameterizing and adapting the system are disclosed.
Roland Sperlich from Rockwall, TX, age ~46 Get Report