.2 ~ 18ghz Cnc Wide-bandwidth The Magnetic Modulation Band-pass Filter Component Technology Research

The systems widely apply frequency agility technology to avoid reconnaissance and interference, this technology have very broad working frequency. Because of the broad 3dB bandwidth of the magnetic tunable bandpass filter modules, they are designed in instantaneous bandwidth receivers, to quickly capture the frequency agility signal. It is difficult to cover the working frequency of 2-18GHz by using a single broadband filter. The traditional way is to use two magnetic tunable filters separately (2-6GHz and 6-18GHz), and assembly two independent digital drivers. Making the system as compact as possible is a trend for all electronics industry. Integrating one digital driver and with the size of one single band pass filter to cover the full frequency range of 2-18GHz plays an important role to lower the size and weight, as well as the power consumption.The main purpose of this article is to realize covering full band of 2-18GHz frequency range by one single broadband filter, and meet all technical specifications. The 2-18GHz digital controlled broadband tunable band pass filter module is combined by a magnetic tunable bandpass filter and its digital driver which controlled the filter by 14 Bit TTL.The filter part is integrated by 2 filters and 2 switches. Among them, the 2-6GHz broadband tunable filter is the most difficult to produce, it used unconventional strong coupling technology of poly crystal spheres. The 6-18GHz broadband tunable filter adopts high magnetic moments spheres with whole loop coupling, and reducing the distance between resonating spheres, etc. The two filters are all designed under the same magnetic pole, the air gap of the magnetic pole is designed in ladder shape, the switch is also integrated inside of the filter to realize the miniaturization of the 2-18GHz broadband tunable filter. The digital driver mainly includes the switch driver and filter driver, the switch driver controls the switching between two broadband bandpass filters; the filter driver controls instantaneous passband frequency of the filters.Based on the above, this paper described the design of 2-18GHz broadband digitally tuned bandpass filters, their digital drivers, and how the modules work.