| 摘要 |
The invention relates to ultrawide-band pulse generators, particularly for radio communication at frequencies of 2 to 11 GHz. The generator includes an oscillator, providing an output signal at a carrier frequency F0, followed by a radiofrequency switching transistor (SW, SW') and a control circuit (CTRL) that controls the gate of the transistor so as to make said transistor conductive for a duration T corresponding to the desired duration of an UWB pulse. The control circuit is arranged so as to consecutively apply, during a single UWB pulse, a first gate voltage VL that makes the transistor conductive with a first internal resistance value during a first portion of the duration T, then at least one second gate voltage that makes the transistor conductive with a second internal resistance value, different from the first value, during a second portion of the duration T. Said internal resistances cause a different attenuation of the oscillation, during the duration T of the pulse, thus enabling the spectrum of the pulse to be controlled so as to help keep same within the spectrum sizes set by radio communication standards. |
