Method and apparatus for characterizing a radio transmitter
AssigneeThe Boeing Company
InventorPhilip J. Ferrell
Life of this patent
Estimating the term…
Abstract
A method and apparatus for identifying a radio transmitter. The transient frequency or phase history of the turn-on characteristics of a transmitter is detected and digitized. The history can be analyzed by a microprocessor operating a computer program to gather transient phase information from an unknown transmitter and to classify the transmitter in accordance with a transient characteristic.
Claims20
Apparatus for determining transient characteristics of a radio transmitter that transmits a transient signal, comprising:
- means for receiving the transient signal transmitted by the transmitter;
- means for measuring the signal phase of the transient signal with respect to a predetermined frequency;
- and
- means for analyzing the signal phase of the transient signal to determine transient characteristics of the radio transmitter.
Apparatus for determining transient characteristics of a radio transmitter than transmits a transient signal, comprising:
- means for receiving the transient signal transmitted by the transmitter;
- means for measuring the difference between instantaneous frequency of the transient signal and a predetermined frequency;
- and
- means for analyzing the frequency difference to determine transient characteristics of the radio transmitter.
Apparatus for determining transient characteristics of a radio transmitter that transmits a transient signal during an extreme portion of a transmission, comprising:
- means for receiving the transient signal transmitted by the transmitter for a period of time including the extreme portion of the transmission;
- means for measuring the signal phase with respect to a predetermined frequency during the period of time;
- and
- means for analyzing the signal phase to determine transient characteristics of the radio transmitter.
Apparatus for determining transient characteristics of a radio transmitter that transmits a transient signal during an extreme portion of a transmission, comprising:
- means for receiving the transient signal transmitted by the transmitter for a period of time including the extreme portion of the transmission;
- means for measuring the difference between instantaneous frequency of the signal and a predetermined frequency during the period of time;
- and
- means for analyzing the frequency difference to determine transient characteristics of the radio transmitter.
Apparatus for determining transient characteristics of a radio transmitter after it is turned on, the radio transmitter operating substantially at a predetermined frequency, comprising:
- means for receiving a transient signal transmitted by the transmitter for a predetermined period of time beginning when the radio transmitter is turned on;
- a frequency discriminator for measuring the phase response of the transient signal with respect to the predetermined frequency during the predetermined period of time;
- and
- means for analyzing the transient signal phase to determine turn-on transient characteristics of the radio transmitter.
Apparatus for determining transient characteristics of a frequency-modulated radio transmitter after it is turned on, the radio transmitter operating substantially at a predetermined carrier frequency, comprising:
- means for receiving a transient signal transmitted by the transmitter for a predetermined period of time beginning when the radio transmitter is turned on and producing a transient phase signal representative of the phase of the transient signal with respect to the predetermined carrier frequency during the predetermined period of time;
- means for detecting the predetermined carrier frequency in the transient signal and producing a start signal in response thereto;
- means for sampling the transient phase signal for the predetermined period of time in response to the start signal;
- storage means for storing data;
- and
- microprocessor means for analyzing the samples of the transient phase signal to determine characteristic data of the turn-on transients of the radio transmitter and for storing the characteristic data in the storage means.
A method for determining transient characteristics of a radio transmitter that transmits a transient signal, comprising the steps of:
- (a) receiving the transient signal transmitted by the transmitter for a period of time;
- (b) passing the transient signal through a frequency discriminator;
- and
- (c) analyzing the frequency-discriminated transient signal to determine transient characteristics of the radio transmitter.
A method for determining transient characteristics of a radio transmitter that transmits a transient signal, comprising the steps of:
- (a) receiving the transient signal transmitted by the transmitter for a period of time;
- (b) measuring a parameter of the transient signal;
- and
- (c) sampling the phase of the transient signal and digitally filtering the samples to determine transient characteristics of the radio transmitter.
Apparatus for determining transient characteristics of a frequency-modulated radio transmitter that transmits a transient signal after it is turned on, the radio transmitter operating substantially at a predetermined carrier frequency, the apparatus comprising:
- means for receiving the transient signal transmitted by the transmitter for a period of time beginning when the radio transmitter is turned on and producing a signal representative of the difference between instantaneous frequency of the signal and a predetermined frequency during the period of time;
- means for detecting the frequency difference represented by the frequency difference signal and producing a start signal in response thereto;
- means for sampling the frequency difference signal in response to the start signal;
- storage means for storing the parametric signal samples;
- and
- microprocessor means for analyzing the frequency difference signal samples to determine characteristic data of the turn-on transients of the radio transmitter and for storing the characteristic data in the storage means.
Dependencies are inferred from the claim text.