| In the high-energy physics and astrophysics experiments, the single events are of nanosecond-grade or even picosecond-grade risetime, so the transient sampling method of ultrafast electronic pulse (picosecond-grade risetime and single pulse) has been become a very important scientific problem, and Picosecond electronics has been naturally introduced as a new electronical science. At present the transistor cutoff frequencies based in the GaAs/InP materials have approached 350 GHz, and 100 GHz monolithic millimeter-wave integrated circuits (MIMIC) have been reported. So these ultraspeed devices and picosecond pulse transmission line can be used in the accurate & low cost measurement of the single ultrafast electronic pulse.In this thesis, according to the principle of real-time sampling and electronic fast-pulse sampling, the main study object is picosecond pulse transmission line and high speed transient sampling gate. So the theory, method and experiment of picosecond electronic pulse transient sampling are stuided.The main results are as follows:1. The problems of transmission line sampler are investigated. A new high-speed sampling plan of miniaturization, integration and solidification is put forward.2. The sampling transmission line theory and method of picosecond electronic pulse measurement are studied in detail. The parameter calculation and the loss analysis of transmission line are discussed. It is pointed out that the basic structure of high-speed sampling transmission line is composed of two positive-negative balanced strobe transmission lines and a signal transmission line at the same direction, and the basic problem of transmission line is the impedance matching. A novel method and model of partial impedance matching of signal transmission line is presented and the computing formula for compensation is deduced. The stepped characteristic impedance matched model and computing formula of strobe transmission lines are put forward too. The picosecond pulse transmission line produced with Polytetrafluoroethylene substrate and multi-layer graphics technology has a risetime of 104 ps and bandwidth of 4 GHz. 3. The theory and method of high speed transient sampling gate are studied. A new four-schottky-diodes balanced sampling gate circuit with symmetric design is developed. The formula of sampling rate and the calculating method of effective strobe width are given.4. The principle and model of high-speed pulse buffer-holding is investigated. The basic model of charge-holding capacitor network is presented, and the design of active buffer-holding network is put forward.5. The methods and technology of high speed sampler are studied in detail. The design of unit circuits, microwave cavity and PCB technology are given. And the prototype of 100 ps high-speed sampler has been developed.By theoretical analysis, calculation, computer simulation and experimental test, the prototype based on this thesis has the function of high-speed transient sampling, sample buffer-slowing holding, multiplex read-out of samples and output gain amplification.The tested waveforms of single fast pulse produced in TD-1110C pulse generator for comparison show that the waveform measured by the sampler is the same as that by high speed oscillograph. The test shows the real rising edge of pulse and the main specification of sampler is: single-shot pulse, sampling interval of 100 ps, sample rate of 10 GSa/s, input impedance of 50Ω, and sample bandwidth of 2.7 GHz. So the prototype should be meet the measurement requirement of high-speed electronic pulse for national physics experiments.The sampling theory and method in this thesis will be the research basis of the single integrated sampling device in the next step, and will be extended to terahertz electronics in the future. It provides an accurate & low cost electronical measurement for many physical experiments and helps to the scientific explanation of the basic physical problems and phenomena.
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