1 Introduction
2 Methodology
2.1 Frequency conversion method of symmetrical dual band
2.2 Synthesis method of N-order cross-coupling matrix
3 Results and discussion
3.1 Basic parameters of dual-band filter
3.2 Design and simulation of symmetrical dual-band filter
Functions | Transmission zeros, the roots of P(Ω) | Reflection zeros, the roots of F(Ω) | Transmitting or reflecting singularities, the roots of E(Ω) |
---|---|---|---|
1 | − 1.5j | − 0.9424j | − 0.7964 + 1.020j |
2 | 1.5j | 0.9424j | − 1.2310 + 0.1914j |
3 | − ∞ | − 0.4299j | 0.7964 + 1.020j |
4 | ∞ | 0.4299j | 1.2310 + 0.1914j |
Functions | Transmission zeros, the roots of P(Ω′) | Reflection zeros, the roots of F(Ω′) | Transmitting or reflecting singularities, the roots of E(Ω′) |
---|---|---|---|
1 | 1.175j | 0.5097j | − 0.0656 + 1.066j |
2 | 0.4254j | − 0.9809j | − 0.0656 − 1.066j |
3 | − 0.4254j | 0.9809j | − 0.1711 + 0.5115j |
4 | − 1.175j | − 0.5097j | − 0.2941 + 0.8791j |
5 | 0 | 0.6078j | − 0.2941 − 0.8791j |
6 | 0 | − 0.6078j | − 0.0287 − 0.4673j |
7 | – | − 0.8227j | − 0.1711 − 0.5115j |
8 | – | 0.8227j | − 0.0287 + 0.4673j |