| 摘要 |
A phased-array RF pulse generator 90 comprises a video-pulse generator 20 arranged to generate video pulse, i.e. electrical pulses having a top-hat shape (60, fig.2b). An array of nonlinear and dispersive transmission lines 130a-c is arranged to generate RF pulses (fig.2c) from the video pulses. The RF pulses may be at microwave frequencies. At least one sensor 165a-c is arranged to detect the leading edge of the video pulses after they have passed along the transmission lines 130a-c. A phase controller 160 is arranged to set the velocity of the video pulses (60) in each transmission line (130a-c) to put the detected leading edges, and hence the generated-RF pulses, into a desired-phase relationship. The phase controller 160 includes a time to digital converter (TDC) which calculates the time difference between two or more signals edges which may sensed at an input sensor 155 and at output sensors 165a-c. The arrangement avoids the cost and bulk of a traditional multi-channel ADC based control system. |
