Fig. 1. The dual-channel meander-line SWS

Fig. 2. The dispersion curves with different b

Fig. 3. The dispersion curves with different substrate materials

Fig. 4. The coupling impedance versus frequency

Fig. 5. Schematic of the dual-channel TWT

Fig. 6. The changes made to achieve impedance matching

Fig. 7. The S-parameters of the high-frequency system

Fig. 8. The output signal and the FFT result

Fig. 9. The output power and corresponding gain versus frequency

Fig. 10. The output power versus the input power

Fig. 11. The output signal of two channels at different frequency

Fig. 12. The experiment system

Fig. 13. The interface adapter to VNA

Fig. 14. The SWS with Rogers 5880

Fig. 15. The measured S-parameters with Rogers 5880

Fig. 16. Test results of the reflection and transmission coefficient