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Application of Microwave Integrators for Interference Suppression

By Lin-Chuan Tsai
Progress In Electromagnetics Research C, Vol. 72, 123-132, 2017


In this study, a trapezoidal-rule integrator and inverting a differentiator are employed to form the transfer function of an approaching integrator in the Z domain. The integrator was implemented to verify the feasibility of the technique, and the integrator exhibited an operating frequency of 1.45 to 6 GHz. Adding microwave integrators to a receiver's radio frequency (RF) circuits in a communication link improves the signal-to-noise ratio (SNR). As a result, an experimental environment was constructed in a wireless local area network (WLAN) band (2400 to 2483.5 MHz). In addition, the RF transmitter emitted the main signal at 2.45 GHz, which included the high-frequency interfering signals at 3.5, 4.5, and 5.5 GHz. The integrators and low-pass filters were implemented to perform signal analysis of the RF signals. To compare the interference suppression of the integrators with the interference suppression of the original and low-pass filters, the receiving power of the main signal and the interfering signals from the different frequencies in the end of the receiver were analyzed. The experimental results indicated that inserting integrators into RF circuits improved the SNR of the communication link by up to 10 dB.


Lin-Chuan Tsai, "Application of Microwave Integrators for Interference Suppression," Progress In Electromagnetics Research C, Vol. 72, 123-132, 2017.


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