A Millimeter-Wave Wideband Frequency Conversion Module Based on Waveguide Switched Filters

Authors：Zhou, Lixue; Feng, Wenjie^*; Zhang, Nan; Chang, Jin; Lu, Jia

Source：IEEE Transactions on Circuits and Systems II: Express Briefs , 2020, 67(12): 3028-3032.

DOI：10.1109/TCSII.2020.2998499

• Bandpass filter (BPF)
• frequency conversion
• millimeter wave (MMW)
• switched filters
• spurious signal
• thin film technology

A wideband frequency conversion module operating at millimeter-wave (MMW) band is proposed in this brief. By up-converting the input intermediate frequency (IF) of 6 GHz with the local oscillator (LO) signal of 13 similar to 17 GHz, it can generate the output radio frequency (RF) signal of 32 similar to 40 GHz. Firstly, to distinguish the exact position of RF signal from unwanted signal, the detailed spectrum simulation is performed based on the MMW mixer model. After that, some in-band interference signals of 2LO, 3LO-IF and 2LO+2IF overlap with the output RF range are found. To address the issue, a wideband filter is added in LO path to reject LO and 3LO. And more importantly, a switchable waveguide filter integrated in the module is designed to divide the whole RF working band into three sub-bands, thus guaranteeing the output spectrum purity. Through the final measurement, the RF signal power of 6.9 similar to 8.5 dBm and the spurious rejection level of 55 dB is obtained.

• Institution
  Nanjing University of Science and Technology