Meta-networks: Reconfigurable cable network topologies for interference control

The importance of filters in signal processing abound in real-life applications such as audio electronics and power distribution networks. We introduce an efficient concept of constructing reconfigurable cable networks for interference control. The method utilises quantum-graph formalisms on composite nodes to implement reconfigurable, compact, wideband filters. By using a cascade of loop networks as building blocks, we show that such meta-networks can provide a flexible way of suppressing unwanted signals thereby increasing the efficiency of the underlying networks.Numerical results show that microwave interference can be filtered to allow only specific narrow (or wide) band frequencies to be fully transmitted while suppressing the other frequency bands. For example, a wave of frequency 0≤ f≤ 6 GHz can be filtered using a cascade of three-loop networks with cable lengths 0.0001 ≤ l ≤ 0.05 m. By tuning one of the constituent cables, we are able to achieve maximum power transmission on a specific set of frequencies while completely suppressing signals of unwanted frequencies. The present paper shows how to implement narrow-, medium- and wide-band bandpass filters by adopting a simple and easy-to-design cable topology for the reconfigurable filter. The proposed solution can be easily integrated with solutions, including varactor diode and phase-shifter based architectures, to achieve practical implementations.