Research And Design On Microstrip Power Divider

The function of the power divider is to divide the power of input and transfer it to another devices. The designers usually put a filter in front of the input port of the power divider and put two filters behind the output ports of the power divider, which can avoid the interference of harmonic frequency. The Wilkinson power divider for harmonic suppression is presented to avoid the external filters.Firstly, the development of Wilkinson power dividers having function of filter is introduced in the thesis. According to the development of it, related plans are arranged. Then three dividers are completed. The content is as follows:1. The power divider having the stub for harmonic suppression is presented, which integrates Wilkinson power divider with low pass filter and uses the stubs for harmonic suppression. The results are presented: the function in the passband is good, and the return loss at the center frequency in the passband is 29.40dB; the function in the stopband is good, and the suppression of signal at the second and third harmonic frequency is 37.15 dB and 57.63 dB, respectively; the suppression of signal whose frequency is from the second harmonic frequency to third harmonic frequency is more than 20 dB.2. The second structure is to integrate Wilkinson power divider with low pass filter, which uses the SIRs stub for harmonic suppression. The results are presented: the function in the stopband is good, and the suppression of signal at the second and third harmonic frequency is 54.26 dB and 56.01 dB, respectively; the suppression of signal whose frequency is from the second harmonic frequency to third harmonic frequency is more than 35 dB.3. The third structure is to integrate Wilkinson power divider with low pass filter which uses the harmonic circle for harmonic suppression. The results are presented: the function in the passband is good, and the return loss at the center frequency in the passband is 25.58dB; the function in the stopband is good, and the suppression of signal at the second and third harmonic frequency is 46.42 dB and 30.06 d B, respectively; the suppression of signal whose frequency is from the second harmonic frequency to third harmonic frequency is more than 25 d B.