Research On Energy Transmission Of Millimeter Wave Chip And Design Of UWB Filters

Since the US Federal Communications Commission (FCC) authorized the unlicensed use of ultra-wideband (UWB) band (3.1-10.6GHz), demand for high-performance ultra-wideband filter has been growing. In this paper, a variety of ultra-wideband band-pass filter structures are proposed. They have compact size, high selectivity, broad upper stopband and other characteristics. In addition,in recent years, 60GHz communications has been developed rapidly. But be-cause oxygen ions in the air can absorb 60GHz electromagnetic waves, the waves cannot transmit at long distance. Based on this phenomenon, some re-searchers proposed to use metal tunnel to transmit 60GHz signal. In this paper, a series of simulation experiments will be carried out to investigate the signal transmission in metal tunnels.Firstly, a ultra-wideband filter based on a multi-mode resonator (MMR) is proposed. This filter has a high return loss in the passband and stopband outside of the passband. This filter consists of a rectangular MMR, which was fed by using coupled lines. The resonant modes of the multimode resonator are ana-lyzed using the even- and odd- mode analysis and four resonant frequencies are obtained. The broadband band-pass filter designed has a relative bandwidth of 96.1% (3.3 GHz to 9.4 GHz) with insertion loss less than 0.9 dB and return loss greater than 15 dB. Stopband is up to 15GHz with a rejection better than 20dB .Secondly, a ultra-wideband filter based on a cascading BPF and BSF is proposed. The proposed filter topology utilizes embedding individually designed short-circuited stub band-pass structures and ring band-stop filter (BSF) into each other. The quarter-wave short-circuited stubs are used to realize the UWB response and the ring BSF is employed to achieve the upper stopband and sup-press the undesired spurious passband. The final UWB BPF is designed with 116% (2.7 to 10.1) GHz relative bandwidth and small size of 12.5×5 mm2. The insertion loss is less than 3 dB in the pass band and less than 0.4 dB at the center frequency. The upper stopband is extended to 21.6 GHz. The group delay is flat with maximum of 0.26 ns. Good agreement is obtained between the simulated and measured results.Thirdly, a ultra wideband filter based on transversal-signal conception is proposed. The ultra-wideband filter is made of a pair of parallel-coupled line and two ring MMRs. We will first analyze the passband performance using trans-mission matrix, and then analyze the characteristics of the ring MMR. We will find the ring MMR creates two mode in passband to widen the UWB response and two transmission zeros outside the passband to form good stopband charac-teristics. The final results showed that this filter has a compact size of 12.5×5mm2,a FBW of 107.7%, passband RL of 13.7dB and a stopband up to 24.6GHz. Compared previously designed filters, this one is competitive.Fourthly, a compact MMR/coplanar waveguide UWB filter based on transversal signal conception is proposed. The proposed filter topology utilises two signal paths with different electrical lengths made up of two wideband BPFs that are connected in parallel. The mechanism of generating notch-band is de-lineated based on transversal signal-interaction concepts. The simulation results show that this UWB filter has a FBW 117% (3.2GHz-12.3GHz) and a sharp notch at 5.8GHz. The filter is fabricated on a substarte Rogers R03003 with di-electric constant of 3.38 and thickness of 0.787mm. The final results show that this filter is rather competitive with other filters.Finally, it is a project to explore the signal transmission in a metal tunnel.The specific work scene is that a chip which contains a microstrip antenna sends electromagnetic signal of 60GHz to feed a rectangular waveguide. The chip is placed near the waveguide port at one end, making the waveguide to conduct electromagnetic signals to the other end. In [1], the researcher found that the transmission efficiency was not desirable and made an assumption that it was the high-order modes that influenced the transmission efficiency. In this papper,we will use a dipole to replace the chip and by changing the way that the dipole feeds the waveguide and observing the receiving of the other end, we testified that there is no influence of higher-order modes on transmission.