Efficient driving circuit for large-current radiator

• US 5,365,240 A
• Filed: 11/04/1992
• Issued: 11/15/1994
• Est. Priority Date: 11/04/1992
• Status: Expired due to Fees

• Current Assignee: Geophysical Survey Systems, Inc.
• Original Assignee: Geophysical Survey Systems, Inc.
• Inventors: Harmuth, Henning F.
• Primary Examiner(s): Hajec, Donald
• Assistant Examiner(s): LE, HOANGANH T
• Application Number:
  US07/971,195
• Time in Patent Office: 741 Days
• Field of Search: 343/701, 343/749, 343/850, 343/858, 343/876, 307/246
• US Class Current: 343/701
• CPC Class Codes: H01Q 17/001 for modifying the directional characteristic of an aerial
• CPC Class Codes: H01Q 3/24 varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching

Abstract

An improved driving circuit for a large-current radiator avoids the need to dissipate large powers in the driving circuit by drawing a certain energy value from a power supply to a storage capacitor and then feeding this energy to the radiating antenna. A constant current source provides, when a switching circuit coupled to the radiator is opened, a current to counter the tendency of the radiator otherwise to maintain continuity of current through the switching circuit, keeping to a minimum the voltage across the switching circuit so that essentially no energy will need to be dissipated in the driving circuit. By choosing the stored energy value carefully one can make it just large enough to cover the radiated energy but leave essentially no energy to be dissipated in the radiator driving circuit.

Claims

1. In a circuit for driving a large-current radiator, the circuit being of a type having at least a first switching circuit, coupled to the radiator, for switching a current pulse through the radiator over a short time, the improvement comprising:

a) a means for feeding a stored limited energy to said switching circuit, said means for feeding including a means for storing the limited energy; and

b) a means for providing a constant current through the radiator, without creating a large voltage across said switching circuit, thereby avoiding the dissipation of a substantial part of the stored limited energy in the switching circuit.

2. A driver circuit, as recited in claim 1, wherein the means for storing limited energy includes at least one capacitor.

3. A driver circuit, as recited in claim 2, wherein the means for storing limited energy includes a means for choosing the amount of energy to be just large enough to be dissipated in the radiator, and leaving essentially no energy to be dissipated in the driver circuit.

4. A circuit for driving a large current radiator, the circuit having first and second switching circuits, coupled to the radiator, for switching a current pulse through the radiator to permit the radiation of a sequence of continguous pulses of the same polarity, comprising:

a) a first and second means for feeding to each of said first and second switching circuits, respectively, in an alternating sequence, stored limited energy, said first and second means for feeding respectively including a first and second means for storing limited energy; and

b) first and second means for providing a constant current through the radiator, without creating a large voltage across the respective switching circuits, thereby avoiding the dissipation of a substantial part of the stored limited energy in the first and second switching circuits.

5. A driver circuit, as recited in claim 4, wherein the first and second means for storing limited energy include at least one capacitor, and a means for discharging said at least one capacitor of one means for storing while recharging said at least one capacitor of the other means for storing.

6. A driver circuit, as recited in claim 5, wherein the first and second means for storing limited energy include a means for choosing the amount of energy to be just large enough to be dissipated in the radiator, and leaving essentially no energy to be dissipated in the driver circuit.

7. A method for driving a large-current radiator circuit, the circuit having at least a first switching circuit coupled to the radiator, comprising the steps of:

drawing a limited energy value from a power supply;

storing the limited energy value in a storage capacitor;

feeding the stored limited energy to the large-current radiator; and

providing a constant current through the radiator, without creating a large voltage across the switching circuit, in response to an opening of the switching circuit.

8. The method of claim 7, further comprising the step of choosing the stored limited energy to be substantially the same as the amount the large-current radiator is designed to radiate.

9. A method for driving a large-current radiator having first and second switching circuits, coupled to the radiator, comprising the steps of:

feeding to each of the first and second switching circuits, respectively, in an alternating sequence, stored limited energy; and

providing a constant current through the radiator, without creating a large voltage across either one of the first and second switching circuits, in response to an opening of either one of the first and second switching circuit.

10. The method of claim 9, further comprising the step of choosing the stored limited energy to be substantially the same as the amount the large-current radiator is designed to radiate.