Donald G Bradley

US Patent:

6356810, Mar 12, 2002

Filed:

Oct 29, 1998

Appl. No.:

09/182385

Inventors:

Donald A. Bradley - Morgan Hill CA

Assignee:

Anritsu Company - Morgan Hill CA

International Classification:

G05D 1902

US Classification:

700298, 331 18, 331177 R

Abstract:

A frequency reference is employed to correct a frequency error in a signal synthesizer. The frequency reference provides a reference frequency with a parts per million deviation from the references nominal frequency. The reference frequency parts per million deviation is equal in magnitude to the parts per million deviation of the frequency error from a desired signal synthesizer output frequency. The deviation in the reference frequency offsets the deviation from the desired output frequency to significantly reduce the frequency error. The frequency reference includes a voltage controlled oscillator, programmable voltage generator, and voltage control engine. The reference frequency is set by the voltage controlled oscillator in response to a frequency setting voltage from the programmable voltage generator. The voltage control engine is coupled to the programmable voltage generator to provide a voltage setting value that controls the frequency setting voltage.

US Patent:

6384772, May 7, 2002

Filed:

May 1, 2000

Appl. No.:

09/562818

Inventors:

Donald A. Bradley - Morgan Hill CA

Assignee:

Anritsu Company - Morgan Hill CA

International Classification:

G01S 740

US Classification:

342172, 342165, 342169, 342170, 375371, 375373, 375376, 455119, 331 1 R, 331 2, 331 16

Abstract:

A linear phase detector circuit enables locking of two frequency sources which can operate in the range of 10 GHz with a minimal frequency offset, such as from 0 Hz to 50 KHz. With the frequency sources operating at frequencies F and F with an offset F -F or F -F the phase detector generates a DC signal indicating a phase offset between a signal F -F or F -F derived from the frequency sources and a reference operating at the desired offset F -F or F -F while eliminating any 2(F -F ) or 2(F -F ) component. In this way, the phase detector allows a substantially higher loop bandwidth than the offset F -F or F -F and allows phase tracking independent of the offset. The phase locking circuitry is useful in applications such as providing a variable Doppler shift in a radar signal.

US Patent:

6417703, Jul 9, 2002

Filed:

Sep 25, 1996

Appl. No.:

08/719763

Inventors:

Donald A. Bradley - Morgan Hill CA

Assignee:

Anritsu Company - Morgan Hill CA

International Classification:

H04K 100

US Classification:

327105, 327113, 455 76

Abstract:

A frequency synthesizer including a divide by R frequency divider providing a first input of a phase detector, a divide by N frequency divider providing a second input of the phase detector, and a voltage control oscillator (VCO) receiving the output of the phase detector and providing an input to the divide by N frequency divider, the VCO output signal being transitioned by varying the frequency division number R. The frequency division number N may also be varied to transition the VCO output signal frequency. A reference oscillator provides an input to the variable R frequency divider and may have its frequency varied to limit resolution error. For greater resolution, multiple frequency synthesizers with divide by R and N frequency dividers having variable frequency division numbers may be connected using mixers to provide a âratio sumâ synthesizer having an output frequency proportional to a sum of N/R ratios.

US Patent:

6700531, Mar 2, 2004

Filed:

Jul 17, 2002

Appl. No.:

10/198451

Inventors:

Ramzi Abou-Jaoude - Santa Clara CA
Donald Bradley - Morgan Hill CA
Karam Noujeim - Sunnyvale CA
David Geller - San Jose CA
Martin I. Grace - San Jose CA

Assignee:

Anritsu Company - Morgan Hill CA

International Classification:

H01S 740

US Classification:

342165

Abstract:

An automotive radar test system includes circuitry for multiple down and up conversions of a signal from the automotive radar. Conditioning circuitry delays an intermediate frequency signal (IF ) obtained after a second down conversion to simulate the delay of a return signal from an object located a particular distance from the automotive radar, and to attenuate the IF signal to simulate variable target sizes, and to generate a Doppler shift in the IF signal to simulate target speed. The conditioned signal is up-converted and transmitted back to the automotive radar system to determine if the automotive radar provides accurate readings for distance, size and speed. The radar test system further couples the second IF signal to a spectrum analyzer to determine if the automotive radar is operating in the desired bandwidth and to a power meter to determine if the automotive radar is transmitting at a desired power level.

US Patent:

6888342, May 3, 2005

Filed:

Sep 4, 2001

Appl. No.:

09/947188

Inventors:

Donald A. Bradley - Morgan Hill CA, US

Assignee:

Anritsu Company - Morgan Hill CA

International Classification:

G01R023/00

US Classification:

324 7619, 324 7622

Abstract:

A spectrum analyzer is combined with the VNA in a housing measuring approximately 4 pounds with the spectrum analyzer portion operating from slightly above DC to above 3. 0 GHz. The components for the spectrum analyzer are provided on a separate printed circuit board from the two printed circuit boards for the display and VNA components in the housing. The design of components for the printed circuit board enable a significant reduction of size from a typical spectrum analyzer which weighs 40 pounds or more and measures on the order of 2 feet by 3 feet by 0. 5 feet.

US Patent:

6917892, Jul 12, 2005

Filed:

Sep 16, 2002

Appl. No.:

10/244291

Inventors:

Donald Anthony Bradley - Morgan Hill CA, US
Kirby Garyen Hong - San Jose CA, US

Assignee:

Anritsu Company - Morgan Hill CA

International Classification:

G06F019/00

US Classification:

702107

Abstract:

A method and apparatus are used to calibration a Vector Network Analyzer (VNA). The method includes providing a calibration module with a single port, providing within the calibration module a set of reflecting components with known scattering parameters, providing control signals to the calibration module through the single port, providing the known scattering parameters to the VNA through the single port, coupling one of reflecting components to the VNA, measuring scattering parameters, and comparing the measured scattering parameters with the known scattering parameters. The apparatus includes a calibration module and a controller module. In one embodiment, the calibration module includes a set of reflecting components, a memory that stores the characterization data, and a current source which sends characterization data in the form of current pulses to the controller module. The controller module includes a voltage source that generates the control signals used by the calibration module.

US Patent:

7019510, Mar 28, 2006

Filed:

Dec 14, 2004

Appl. No.:

11/011923

Inventors:

Donald Anthony Bradley - Morgan Hill CA, US

Assignee:

Anritsu Company - Morgan Hill CA

International Classification:

G01R 23/14
G01R 27/32

US Classification:

324 7623, 324642

Abstract:

A handheld Vector Network Analyzer (VNA) is provided with circuitry capable of providing operation over a very wide bandwidth. The VNA includes two reflectometers, a first high frequency reflectometer () such as the model S331 Site Master™ and a second lower frequency reflectometer () such as the model S820 Site Master™, both the S331 and S820 being manufactured by Anritsu Company of Morgan Hill Calif. The high frequency reflectometer () includes a forward coupler () having a coupling path connected to a high frequency impulse signal source (), and a through path connecting the test port () and incident and reflected signal measurement couplers () to a load (). To connect the high and low frequency reflectometers (), a diplexer () is connected between the load () and an output of the low frequency reflectometer (). The diplexer () includes an inductor () for blocking high frequency signals from the low frequency reflectometer (), and a capacitor () preventing a low frequency signal path through the load () to ground while providing an impedance matching the load () to high frequency signals.

US Patent:

7054776, May 30, 2006

Filed:

May 11, 2005

Appl. No.:

11/126668

Inventors:

Donald Anthony Bradley - Morgan Hill CA, US
Kirby Garyen Hong - San Jose CA, US

Assignee:

Anritsu Company - Morgan Hill CA

International Classification:

G06F 13/24

US Classification:

702107, 702106, 702183, 702188

Abstract:

A method and apparatus are used to calibration a Vector Network Analyzer (VNA). The method includes providing a calibration module with a single port, providing within the calibration module a set of reflecting components with known scattering parameters, providing control signals to the calibration module through the single port, providing the known scattering parameters to the VNA through the single port, coupling one of reflecting components to the VNA, measuring scattering parameters, and comparing the measured scattering parameters with the known scattering parameters. The apparatus includes a calibration module and a controller module. In one embodiment, the calibration module includes a set of reflecting components, a memory that stores the characterization data, and a current source which sends characterization data in the form of current pulses to the controller module. The controller module includes a voltage source that generates the control signals used by the calibration module.