| 摘要 |
A signal splitter 34 is provided, comprising at least four outputs 14, 16, 14' & 16', and a plurality of step-up transformers 36, 36' & 38, wherein each step-up transformer has fewer than seven turns. The first step-up transformer 38 is connected to a common input port 12 and is positioned between the input port 12 and second and third step-up transformers 36 & 36'. The first step-up transformer 38 has a number of turns different from that of the second and third step-up transformers 36 & 36'. The use of transformers with different numbers of turns allows adjustment of impedance within the splitter. By using step-up transformers with fewer turns than the conventional seven turns used in splitters, the bandwidth of the splitter is substantially increased so that the splitter can function for signals of up to at least 2 GHz. The circuit thus overcomes a frequency limitation of about 1200 MHz in prior art splitters that arises from the relatively large leakage inductance and inter-winding capacitance of prior art step-up transformers. The first step-up transformer may be connected to a transmission line transformer and may share a core with it. |
