Band Pass Filters and Diplexers – Meeting the Industry’s Filtering Needs

Being passive, filters and diplexer’s main challenges are improved performance over ever more difficult environmental specs and tighter frequency plans; needed better roll offs, for improving spectral efficiency.

What are BP Filters and Diplexers?

The band pass filters and diplexers encompass a variety of specifications. This leaves the designers to minimize the level of mutual interactions and create parallel connections with the help of optimization routines. Such 3-port diplexersmay additionally require the combination of three or more different frequency bands through one common diplexer or filter. This is used for multiband applications, covering multiple satellite bands, for example.

The BPF allows the mid pass band to travel through it, whereas the band reject filter allowsonly the upper as well as lower bands to travel. Many configurations are possible, maximally flat, steep roll offs requiring increased number of filter poles for example, and higher rejection bands etc.

The Design Strategy

Since optimization routine occupies a crucial role in reducing the level of mutual interaction between final response shaping and filters, here are some of the necessary steps that define its overall strategy –

• Quickly estimates the transfer functions of both the filters • Create net list of filters and diplexers • Carrying out optimization for refining the final responses • Translating the list into preferred technologies for the realization of diplexer

Phase Lock Oscillator – Another Advanced Innovation

A phase lock oscillator is available in diverse frequency range varying exceeding 1 GHz to 42 GHz. It is unmistakably a premium component for higher frequencies in harsh environments.

Improving the overall phase noise performance, while pushing the upper frequency is always a challenge. Additional constraints of vibration resistance, radiation hardened semiconductors and shock, while maintaining the required phase noise is the ultimate challenge for these.