Miniature ultra-wideband active receiving antenna
According to some aspects of this invention, a compact, broadband active receiving antenna uses one or more high transconductance transistors such as Field Effect Transistor(s) paired with another Transistor and arranged in a Cascode amplifier configuration. Some embodiments involve a single high transconductance transistor arranged with a high efficiency transformer in a nondissipative feedback loop to improve linearity and dynamic range. The devices have a high input resistance, low input capacitance, low noise and a very high second and third order Intercept Point. Since the gain is primarily a function of the amplifying electronics, it is not necessary to increase the directivity of the antenna to achieve higher gain.
1. An active radio frequency reception circuit comprising:
a. an antenna probe element adapted to sense an electric field coupled to one of the gate and base of a transistor,
b. one of the source and emitter of said transistor coupled to ground by way of the primary winding of a transformer
c. one of the drain and collector of said transistor coupled to the secondary winding of said transformer thereby creating a passive, nondissipative feedback loop that couples signal energy from said transistor's drain or collector to said transistors source or emitter while also coupling to a radio frequency receiver device.
2. A broad-band active radio frequency reception circuit comprising:
a. an electric-field antenna probe element adapted to sense an electric field;
b. the element coupled to the gate of a FET transistor;
c. the source of the FET transistor coupled to ground; and
d. the drain of the FET transistor coupled in a Cascode arrangement to another transistor that is coupled to a radio frequency receiver device, wherein the broad-band active radio frequency reception circuit is configured for broad-band reception of radio frequency signals.
3. A broad-band active radio frequency reception-circuit according to claim 1 , wherein the circuit is connected to at least one other similar circuit such that the out-put of the active radio frequency reception circuit is coupled to one of the gate and base of a transistor in the at least one other similar circuit.
4. A circuit according to claim 1 further comprising an additional such circuit, the circuits coupled in a differential configuration through the windings of a Balun transformer.
5. A circuit according to claim 2 further comprising an additional such circuit, the circuits coupled in a differential configuration through the windings of a Balun transformer.
6. A circuit for coupling an element adapted to sense an electrical field to a receiver ever a predetermined broad bandwidth of radiofrequency energy, comprising:
a. an electric field probe element adapted to sense an electrical field;
b. a high transconductance FET, whose gate is coupled to the element;
c. wherein the FET source is coupled to ground;
d. wherein the FET drain is adapted to be coupled to a receiver via at least one device which is adapted to enhance signals presented by the circuit to the receiver; and
e. wherein the element is configured so as to be not resonant to the broad bandwidth radiofrequency energy.
7. A circuit according to claim 6 in which said device adapted to enhance signals includes a bipolar junction transistor whose emitter is coupled to the FET drain in a cascade amplifier relationship and whose collector is adapted to be coupled to the receiver.
8. A circuit according to claim 6 in which said device adapted to enhance signals includes a feedback loop between the drain and the source of the FET, which feedback loop includes a transformer having a first side coupled to the FET drain and a voltage source, and a second side coupled to ground and the FET source.
9. A circuit for coupling an element adapted to sense an electrical field to a receiver over a predetermined bandwidth of radiofrequency energy, comprising:
a. an element adapted to sense an electrical field;
b. a high transconductance FET, whose gate is coupled to the element;
c. wherein the FET source is coupled to ground;
d. wherein the FET drain is adapted to be coupled to a to a receiver via;
(i) a bipolar junction transistor whose emitter is coupled to the FET drain in a cascade amplifier relationship and whose collector is adapted to be coupled to the receiver; and
(ii) a feedback loop between the collector of the bipolar junction transistor and the source of the FET, which feedback loop includes a transformer having a first side coupled to the collector of the bipolar junction transistor and a voltage source, and a second side coupled to ground and the FET source; and
e. wherein the element is not resonant to the predetermined bandwidth of radiofrequency energy.
10. A circuit for coupling an element adapted to sense an electrical field to a receiver over a broad-band radiofrequency energy, comprising:
a. a first and a second element adapted to sense an electrical field;
b. for the first element;
(i) a first high transconductance FET whose base is coupled to the first element and whose source is coupled to ground; and
(ii) a first bipolar junction transistor whose emitter is coupled to the drain of the first FET and whose collector is coupled to a transformer;
c. for the second element:
(i) a second high transconductance FET whose base is coupled to the second element and whose source is coupled to ground; and
(ii) a second bipolar junction transistor whose emitter is coupled to the drain of the second FET and whose collector is coupled to the transformer;
d. the transformer including:
(i) a first side coupled to the collectors of each of the two bipolar junction transistors and tapped between the couplings to said collectors to a voltage source; and
(ii) a second side adapted to be coupled to a receiver;
e. wherein the first and second elements are not resonant to the broad-band radiofrequency energy.
11. A circuit according to claim 1 further comprising a television receiver.
12. A circuit according to claim 2 further comprising a television receiver.
13. A circuit according to claim 6 further comprising a television receiver.
14. A circuit according to claim 9 further comprising a television receiver.
15. A circuit according to claim 10 further comprising a television receiver.
16. A circuit according to claim 1 further comprising a consumer electronics device.
17. A circuit according to claim 2 further comprising a consumer electronics device.
18. A circuit according to claim 6 further comprising a consumer electronics device.
19. A circuit according to claim 9 further comprising a consumer electronics device.
20. A circuit according to claim 10 further comprising a consumer electronics device.
21. A circuit according to claim 1 wherein the element is part of a printed circuit.
22. A circuit according to claim 2 wherein the element is part of a printed circuit.
23. A circuit according to claim 6 wherein the element is part of a printed circuit.
24. A circuit according to claim 9 wherein the element is part of a printed circuit.
25. A circuit according to claim 10 wherein the elements are part of a printed circuit.
26. A circuit for coupling an element adapted to sense an electrical field to a receiver over a predetermined broad bandwidth of radiofrequency energy, comprising:
an electric field probe element adapted to sense an electrical field;
a first high transconductance FET transistor, whose gate is coupled to the element and its source is coupled to ground;
wherein the FET drain is adapted to be coupled to a receiver via at least a second transistor which is adapted to enhance signals presented by the circuit to the receiver;
wherein the element is configured so as to be not resonant to the broad bandwidth radiofrequency energy; and
at least one inductive feedback path configured to couple either one or both transistors' drain/collector to their corresponding source/emitter.
27. A circuit according to claim 26 , wherein the second transistor is a FET or a bipolar transistor.
28. A circuit according to claim 26 further comprising a television receiver.
29. A circuit according to claim 26 further comprising a consumer electronics device.
30. A circuit according to claim 26 wherein the element is part of a printed circuit.