| 摘要 |
A method and apparatus for testing the response of a device to RF signals of different frequency generated by apparatus comprising an RF signal generator (26) having at least two modes of operation which entails at least one source change between one mode and the other comprising the step of detecting unwanted electrical noise in the signal transmitted by the device under test by means of a detector (334), amplifiers (336, 338) and compensating for said unwanted electrical noise by signals from a DAC (340), and amplifier (342, 344, 346 and 336) during each mode of operation of the generator. Different compensation is required for the different modes of operation of the RF source, and appropriate compensation is selected by reference to the source in use at the time. |
