| 摘要 |
PURPOSE:To increase the margin against noise, by constituting the multi-frequency receiver through the use of filter in less quantity of hardware, by providing the individual limiter different in the limit level every frequency, at the post stage of the band block filter. CONSTITUTION:At the post stage of the band block filters HEF and LEF, limiters L1LM, L2LM, L3LM, L4LM for low group and limiters H1LM, H2LM, H3LM, H4LM for high group which are different only from the limit level every frequency, are provided. Even if simple filters in which uncertain region of the level performance is several dB are used for HEF and LEF, the guarantee of the ripple in the pass band width of the band block filter can be made every frequency. Thus, HEF and LEF are provided in less amount of hard-ware and multi-frequency receiver is constituted, allowing to increase the margin against noise. |
