CONTINUOUSLY VARIABLE VOLTAGE-CONTROLLED PHASE SHIFTER

• US 3,621,406 A
• Filed: 12/09/1969
• Issued: 11/16/1971
• Est. Priority Date: 12/09/1969
• Status: Expired due to Term

• Current Assignee: Carl E. Johns, Paine,
• Original Assignee: Carl E. Johns, Paine,
• Inventors: Paine,, Carl, E. Johns
• Primary Examiner(s): Roy Lake
• Assistant Examiner(s): James B. Mullins
• Application Number:
  US04/883,528
• Time in Patent Office: 707 Days
• Field of Search: 328/24,104,105,154,155 307/262
• US Class Current: 327/238
• CPC Class Codes: G06F 11/2221 to test input/output devices or peripheral units
• CPC Class Codes: G06K 15/02 using printers
• CPC Class Codes: H03H 7/20 Two-port phase shifters providing an adjustable phase shift

Abstract

A continuously variable phase shifter including a phase splitter which provides four quadrature signals of an input signal, a summing resistor and a phase control diode matrix between the phase splitter and the summing resistor. The matrix includes a separate diode in the path of each of said four signals. The four diodes are connected to two terminals at which DC control voltages are applied to control the states of conduction of the four diodes. The diodes are controlled so that only one diode is fully forward biased when 0*, 90*, 180* or 270* phase shift is desired while two of the four diodes are partially forward biased when a phase shift between any two of the above four values is desired.

Claims

1. A phase shifter comprising:

phase-splitting means responsive to an input signal for providing four signals including first, second, third and fourth signals, each of the same frequency as the input signal, with said first, second, third and fourth signals having phase differences with respect to said input signal of 0*, 90*, 180* and 270*, respectively;

signal summing means; and

phase control diode means including four diodes coupled to said signal-summing means and to said phase-splitting means, with each diode in the path of a different one of said four signals, and;

bias control means connected to said four diodes for controlling the states of conduction thereof, thereby to control the phase shift of the signal summed by said signal-summing means which is a function of said four signals and the states of conduction of said four diodes, with said bias control means being adapted to vary the states of conduction of said four diodes so as to continually vary the phase shift over the entire range from 0* to 360* with three of said four diodes being in a back biased state when the phase shift is n X 90* where n is an integer not greater than four and two of said diodes are in a back biased state when the phase shift is not an integer multiple of 90*.

2. The arrangement as recited in claim 1 wherein said bias control means includes a pair of control terminals, coupled to said four diodes and means for applying two related direct-current control voltages at said control terminals to control the states of conduction oF said four diodes and thereby control the phase of the signal, summed up by said summing means, with respect to said input signal.

3. The arrangement as recited in claim 2 wherein first and second of said four diodes have their anodes coupled to said phase-splitting means and their cathodes to said signal-summing means and third and fourth diodes of said four diodes have their cathodes coupled to said phase-splitting means and their anodes to said signal-summing means.

4. The arrangement as recited in claim 3 wherein one of said terminals is connected to the anode and cathode of said first and third diodes, respectively, and the other control terminals is connected to the anode and cathode of said second and fourth diodes respectively.

5. In a continuously variable phase shifter for shifting the phase of an input signal between 0* and 360*, said phase shifter including a phase splitter which provides four signals consisting of first, second, third and fourth signals which are related to an input signal by phase differences of 0*, 90*, 180* and 270*, respectively, and a signal summer which sums various ones of said four signals to provide an output signal which has the desired phase difference with respect to said input signal, the improvement comprising:

phase control diode means coupled between said phase splitter and said signal summer, said phase control diode means including four diodes, each in the path of a different one of said four signals, and control means including means for applying two related potentials to said diodes to control the states of conduction of said four diodes with at least two of said four diodes being back biased.

6. The arrangement as recited in claim 5 wherein said means applying apply said two related potentials to said diodes so that only one of said diodes is fully forward biased and the other three diodes are back biased when a phase shift of n X 90* is desired, where n equals 0, 1, 2 or 3, and wherein two diodes in the paths of two of said four signals having a phase difference of only 90* are partially forward biased and the other two are back biased when n is other than an integer but less than 4.

7. The arrangement as recited in claim 5 wherein first and second diodes of said four diodes are in the paths of said first and second signals respectively, with the cathodes of said first and second diodes being connected to said signal summer, and wherein third and fourth diodes of said four diodes are in the paths of said third and fourth signals, respectively, with the anodes of said third and fourth diodes being connected to said signal summer, and said control terminal means being separately connected to the anodes of said first and second diodes and to the cathodes of said third and fourth diodes.

8. The arrangement as recited in claim 7 wherein said control means comprises first and second terminals, and means connecting said first terminal to the anode and cathode of said first and third diodes, respectively, and means connecting said second terminal to the anode and cathode of said second and fourth diodes, respectively.