| 摘要 |
1279361 Frequency changers STANDARD TELEPHONES & CABLES Ltd 8 Jan 1971 1014/71 Headings H3F and H3R A frequency changing device comprises an R.F. transmission line e.g. microstrip transmission line terminated in a matched load 9 of length equal to half the carrier wavelength and an arrangement e.g. a pulse distributer 8, switching diodes 5, &c., for simulating cyclic movement along the line of an R.F. energy reflector in a direction and at a rate determining respectively the sense and magnitude of frequency offset of a sideband, and a circulator 2 having input and output ports 3, 4. In operation, an R.F. carrier applied at 3 undergoes different phase shifts as the carrier wave reflected at short circuits caused by the selective switching of diodes 5 has to travel different electrical lengths towards the load at 3. |
