Nanosecond Pulse Source And The Research And Design Of Gps Antenna

Nanosecond and Sub-Nanosecond pulse generator as well as GPS antenna are discussed in the thesis.A nanosecond pulse generator for the medical IEM effects study is designed and fabricated based on the MOSFET and fast response circuit. Experimental results suggest that the parameters of the output pulse are with0.1-1kV quasi-continuously adjustable amplitude,40-200ns section-adjustable falling time,60-220ns pulse duration,20ns rising time,1-5kHz section-adjustable repetition frequency rate (RFR) on a50Ω load and the dimension of the generator is32×30×7cm3. The parameters such as amplitude, pulse duration and RFR are decided by a computor through an authoring software.A sub-nanosecond pulse generator for the pulse radio fuse and fast response circuit application is designed and fabricated based on the stepped recovery diode (SRD) and RLC discharge circuit. The optimal simulation of the generator is accomplished by the PSpice software. Experimental results suggest that the parameters of output pulse are with4V amplitude,600ps pulse duration,10MHz RFR,70-80ps trigger jitter on a50Ω load and the dimension of the generator is69X22X5mm3.An antenna fed by copplar waveguide (CPW) for global position system (GPS) is designed through commercial software (CST MWS). Experimental results suggest that the parameters of antenna are with545MHz bandwidth covering two bands with center frequency of1.227GHz and1.575GHz respectively. These two bands are assigned as the vehicle GPS communication by the FCC. The vlotage standing wave ratio (VSWR) and axial ratio (AR) are less than2and3respectivly. The antenna could meet the requirment for the GPS application.