5G毫米波段升降頻段模組製作與特性研究

Abstract

本研究設計一款可用於5G 毫米波頻段的升降頻模組，中頻端頻率操作於3.5GHz，射頻端則分成28 GHz 和38 GHz 兩個頻率。升降頻模組是根據超外差式架構去做設計，內部的電路包含功率放大器、低雜訊放大器、升降頻混波器、濾波器、壓控振盪器，其中射頻端濾波器是利用基板合成波導技術直接實現於印刷電路板上方便與其他電路元件做連接，而每四組升降頻模組都會搭配一塊的電源電路模組以便供電。經過測試28 GHz的升降頻模組增益可達10 dB以上、頻寬為700 MHz，38 GHz的升降頻模組增益達到18 dB以上、頻寬為700 MHz。 本升頻模組驗證過可用於搭配軟體無線電和陣列天線進行無線傳輸與接收。由軟體無線電所產生的射頻訊號(3.5 GHz)連接至升頻模組再透過陣列天線進行無線的傳輸；另一端則透過陣列天線將所接收到的訊號透過降頻模組將頻率降至中頻訊號(3.5 GHz)，再交由軟體無線電內部解調高速的類比數位、數位類比轉換器和 FPGA，將接收到的訊號直接轉換成同相與正交的基頻訊號。

In this study, an up/down converter module that can be used in the frequency band of 5G millimeter wave has been designed. The IF port can be operated in the frequency band of 3.5 GHz, and the RF port can be operated in the frequency band of 28 GHz and 38 GHz. The up/down converter module is designed based on the idea of the superheterodyne receiver architecture. The internal circuit contains power amplifier, low-noise amplifier, up/down mixer, filter and voltage-controlled oscillator. Moreover, a filter of the RF port is directly installed on the printed circuit board using the substrate integrated waveguide technology to connect to other electronic components easily. Besides, every 4 up/down converter modules are equipped with 1 electric power supply circuit module for the power supply. After performing a test, it was found that the gain of the up/down converter module for the frequency band of 28 GHz can reach above 10 dBm and the gain of the up/down converter module for the frequency bandwidth of 700 MHz 38 GHz can reach above 18 dBm with the frequency bandwidth of 700 MHz. It is tested that this up/down converter module can perform wireless transmission and reception with the software-defined radio and array antenna. The RF signal (3.5 GHz) generated by the software-defined radio is sent to the up converter module, and the array antenna performs the wireless transmission. On the other end, the array antenna sends the received signal to the down converter module, and the module lowers the frequency to IF signal (3.5 GHz). The analog-to-digital converter and FPGA in the software-defined radio then will convert the received signal to become the in-phase and orthogonal baseband signal.