摘要 |
<p>A wide band amplifier for operation at very high frequencies, for example in the 20MHz to 50GHz range comprises a MESFET distributed amplifier (22) having a gate and a drain transmission line, a first hybrid circuit (18) to apply a first and second input signal to opposite ends of the gate transmission line, and a second hybrid circuit (26) connected to opposite ends of the drain transmission line to receive and combine first and second output signals from the drain transmission line to provide an amplified output signal. The use of two input signals travelling in opposite directions along the gate transmission line increases the gain which can be achieved in the distributed amplifer and reduces the noise component of the output signal. It is particularly useful for enhancing the performance of a distributed amplifier containing only a few MESFETS.</p> |