UWB pulse generator

Patent metadata

Field	Value
Publication number	US-9847811-B2
Application number	US-201415034394-A
Country	US
Kind code	B2
Filing date	Dec 17, 2014
Priority date	Dec 18, 2013
Publication date	Dec 19, 2017
Grant date	Dec 19, 2017

Abstract

An ultra-wideband pulse generator, for radio communication at frequencies of 2 to 11 GHz comprises an oscillator providing an output signal at carrier frequency F0 followed by a radiofrequency switching transistor and a control circuit controlling the gate of the transistor to turn it on for duration T corresponding to the desired duration of a UWB pulse. The control circuit is arranged to successively apply, during the same UWB pulse, a first gate voltage turning the transistor on with first internal resistance value for a first part of duration T, a second gate voltage that turns the transistor on with second internal resistance value, different from the first, for a second part of duration T. These internal resistances cause the oscillation to be attenuated differently for duration T of the pulse, allowing the spectrum of the pulse to maintain it within the spectral templates imposed by the radio communication standards.

First claim

The invention claimed is:

1. A UWB pulse generator comprising:
an oscillator that provides an oscillating signal at a carrier frequency F 0 followed by a radiofrequency switching transistor configured for selectively connecting the oscillating signal to an output of the UWB pulse generator and a control circuit that controls a gate of the radiofrequency switching transistor in order to turn the radiofrequency switching transistor it on for a duration of time T that corresponds to a desired duration of a UWB pulse,
wherein the control circuit is arranged so as to successively apply, during one and the same UWB pulse, a first gate voltage that turns the radiofrequency switching transistor on with a first internal resistance value for a first part of the duration T, then at least a second gate voltage that turns the radiofrequency switching transistor on with a second internal resistance value, different from the first value, for a second part of the duration T.

2. The UWB pulse generator of claim 1 , wherein the control circuit comprises:
two logic inverters supplied with a supply voltage that have their outputs connected to a gate of the radiofrequency switching transistor via respective resistors; and
a sequencing circuit that sets up, at an input of the first logic inverter, a first logic signal for turning the radiofrequency switching transistor on and, at an input of the second logic inverter, a second logic signal for turning the switching transistor on, with a partial overlap between the first and the second logic signal, allowing defining at least one period of time during which only one of the two logic signals is at a level for turning the radiofrequency switching transistor on and one period of time during which both logic signals are at this level, the two periods being adjacent.

3. The UWB pulse generator of claim 2 , wherein the oscillating signal generated by the oscillator is a differential signal, and there are two radiofrequency switching transistors that operate symmetrically and are controlled symmetrically by the two logic inverters.

4. The UWB pulse generator of claim 2 , wherein the resistors that are connected between an output of an inverter and the gate of a radiofrequency switching transistor are composed of multiple resistors that are switched in order to select a chosen resistance value.

5. The UWB pulse of claim 2 , wherein the logic inverters are composed of an array of multiple inverters in parallel with different output impedance characteristics, one logic inverter being selected based on desired resistance characteristics and the logic inverters being able to be selectively placed in a high-impedance state if the logic inverters are not selected.

6. The UWB pulse generator of claim 2 , wherein a value of the supply voltage of the logic inverters is modifiable.

7. The UWB pulse generator of claim 1 , wherein the oscillator is a LC oscillator with a pair of differential branches whose operation is switched by application or interruption of a supply current to the pair of differential branches, the generator configured to modify the supply current of the pair of branches during the UWB pulse.

8. The UWB pulse generator of claim 7 , further comprising a current injection circuit configured to inject a current into one of the outputs of the differential branches so as to unbalance said differential branches during a UWB pulse initiation phase in order to impose an oscillation phase upon initiation.

9. A UWB pulse generator comprising:
an oscillator that provides an oscillating signal at a carrier frequency F 0 followed by a radiofrequency switching transistor and a control circuit that controls a gate of the radiofrequency switching transistor in order to turn the radiofrequency switching transistor on for a duration of time T that corresponds to a desired duration of a UWB pulse,
wherein the control circuit is arranged so as to successively apply, during one and the same UWB pulse, a first gate voltage that turns the radiofrequency switching transistor on with a first internal resistance value for a first part of the duration T, then at least a second gate voltage that turns the radiofrequency switching transistor on with a second internal resistance value, different from the first value, for a second part of the duration T,
wherein the control circuit comprises:
two logic inverters supplied with a supply voltage that have their outputs connected to a gate of the radiofrequency switching transistor via respective resistors; and
a sequencing circuit that sets up, at an input of the first logic inverter, a first logic signal for turning the radiofrequency switching transistor on and, at an input of the second logic inverter, a second logic signal for turning the switching transistor on, with a partial overlap between the first and the second logic signal, allowing defining at least one period of time during which only one of the two logic signals is at a level for turning the radiofrequency switching transistor on and one period of time during which both logic signals are at this level, the two periods being adjacent.

10. The UWB pulse generator of claim 9 , wherein the oscillating signal generated by the oscillator is a differential signal, and there are two radiofrequency switching transistors that operate symmetrically and are controlled symmetrically by the two logic inverters.

11. The UWB pulse generator of claim 9 , wherein the resistors that are connected between an output of an inverter and the gate of a radiofrequency switching transistor are composed of multiple resistors that are switched in order to select a chosen resistance value.

12. The UWB pulse of claim 9 , wherein the logic inverters are composed of an array of multiple inverters in parallel with different output impedance characteristics, one logic inverter being selected based on desired resistance characteristics and the logic inverters being able to be selectively placed in a high-impedance state if the logic inverters are not selected.

13. The UWB pulse generator of claim 9 , wherein a value of the supply voltage of the logic inverters is modifiable.

14. The UWB pulse generator of claim 9 , wherein the oscillator is a LC oscillator with a pair of differential branches whose operation is switched by application or interruption of a supply current to the pair of differential branches, the generator configured to modify the supply current of the pair of branches during the UWB pulse.

15. The UWB pulse generator of claim 14 , further comprising a current injection circuit configured to inject a current into one of the outputs of the differential branches so as to unbalance said differential branches during a UWB pulse initiation phase in order to impose an oscillation phase upon initiation.

16. A UWB pulse generator comprising:
an oscillator that provides an oscillating signal at a carrier frequency F 0 followed by a radiofrequency switching transistor configured for selectively connecting the oscillating signal to an output of the UWB pulse generator and a control circuit that controls a gate of the radiofrequency switching transistor in order to turn the radiofrequency switching transistor on for a duration of time T that corresponds to a desired duration of a UWB pulse,
wherein the control circuit is arranged so as to successively apply, during one and the same UWB pulse, a first gate voltage that turns the radiofrequency switching transistor on with a first internal resistance value for a first part of the duration T, then at least a second gate voltage that turns the radiofrequency switching transist

Assignees

• Commissariat Energie Atomique

Inventors

• Masson Gilles
• Hameau Frédéric
• Ouvry Laurent

Classifications

• H04B1/7174

  Pulse generation (in general H04L25/03834) · CPC title

• H04B1/7172 Primary

  Pulse shape (in general H04L25/03834) · CPC title