Bogdan Sadowski

US Patent:

7215936, May 8, 2007

Filed:

Apr 2, 2003

Appl. No.:

10/405269

Inventors:

Bogdan Sadowski - Cary NC, US

International Classification:

H04B 1/10

US Classification:

455215, 455255, 455256, 455259, 4552501, 455296

Abstract:

An improved low-cost super-regenerative receiver includes sampling phase-locked loop. Phase sampling is controlled by the quench signal (). In the preferred embodiment, logic state HIGH to logic state LOW transition of the quench signal () defines the timing for the event of sampling. While the quench signal () is in logic state HIGH, a quenched oscillator is being turned ON and the oscillation amplitude builds-up until a steady-state level is reached. When the oscillator is turned OFF, effective quality factor of an electronically tunable resonator () is reduced, by increasing losses in the circuit, thus to ensure aperiodic (non-oscillatory) decay. The resonator's charge—an energy stored on internal reactive components of the resonator (), which existed at the instant of turning the oscillations OFF, is transferred during precisely defined period of time to the charge holding capacitor () of a charge transfer circuit (). Charge is stored on the charge holding capacitor (), which is also part of a loop filter, until the described here charge transfer cycle is repeated again. A frequency control signal () at the output of the loop filter sets the frequency of the oscillation for the duration of the succeeding oscillator ON time.

US Patent:

8144069, Mar 27, 2012

Filed:

Oct 2, 2008

Appl. No.:

12/243974

Inventors:

Bogdan Sadowski - Cary NC, US
Zofia Sadowska - Cary NC, US

International Classification:

H01Q 9/16
H01Q 1/36

US Classification:

343806, 343895, 343795

Abstract:

A low-cost compact wideband antenna () has two triangular-shaped arms ( and ) formed by winding the conductive wire into a zigzag pattern. The two arms ( and ) form a compact bow-tie type antenna having equivalent electrical size larger then its mechanical dimensions. Two straight wires ( and ) are joined to, and electrically connected between two respective largest segment ends of two zigzag structures. The compact wideband antenna () is hidden inside the decorative household item () to provide antenna having external appearance appropriate for modern home furnishing setting with improved broadband characteristic across VHF and UHF bands but without the inconvenience of the large size.

US Patent:

60160691, Jan 18, 2000

Filed:

Feb 10, 1998

Appl. No.:

9/021668

Inventors:

Bogdan Sadowski - Apex NC

Assignee:

Ericsson Inc. - Research Triangle Park NC

International Classification:

H03L 700
H03L 7093

US Classification:

327156

Abstract:

A phase locked loop includes a controlled oscillator that is responsive to a control signal to generate an output signal, the frequency of which is a function of the control signal. A phase detector is responsive to a reference frequency input signal and to the output signal, to produce an error signal. A loop filter filters the error signal, to thereby produce the control signal. An acquisition sweep circuit is responsive to an activation signal, to sweep the control signal and thereby aid to acquire lock in the phase locked loop. Simultaneous increase in the amplitude of the reference frequency input signal is provided during sweep of the control signal. The increase in amplitude may be provided by a variable attenuation circuit that is coupled between a phase locked loop input signal and the reference frequency input signal, and that is also responsive to the activation signal. The variable attenuation circuit, preferably in the form of a tunable resonant tank notch circuit, attenuates the phase locked loop input signal after the sweep of the control signal, to thereby decrease the amplitude of the reference frequency input signal after the sweep of the control signal. Thus, the amplitude of the reference frequency input signal is higher during the sweep of the control signal, to thereby temporarily widen the bandwidth of the phase locked loop, while temporarily sweeping the control signal.

US Patent:

59458542, Aug 31, 1999

Filed:

Feb 10, 1998

Appl. No.:

9/023667

Inventors:

Bogdan Sadowski - Apex NC

Assignee:

Ericsson Inc. - Research Triangle Park NC

International Classification:

H03B 304

US Classification:

327156

Abstract:

Phase locked loops include a controlled oscillator that is responsive to a control signal, to generate an output signal, the frequency of which is a function of the control signal. A phase detector is responsive to a reference frequency input signal and to the output signal, to produce an error signal. A loop filter filters the error signal, to thereby produce the control signal. A bandpass filter is responsive to the error signal, to produce a filtered error signal at twice the frequency of the reference frequency, and an envelope detector is responsive to the filtered error signal to sense the amplitude of the filtered error signal. A variable attenuation circuit is responsive to the envelope detector output, to variably attenuate a phase locked loop input signal based on the amplitude of the filtered error signal, and thereby produce the reference frequency input signal.