Persons
Article author
- Counter: 387 | Comments : 0
- Counter: 578 | Comments : 0
Currently, for numerical simulation of random processes two types of the random number generators are used. The first type is based on the algorithmic methods for generating pseudorandom numerical sequences. The second type of generators is based on the use of physical sources of noise or of chaotic processes. The first type of generators does not permit to obtain the truly random numerical sequences, and the second type generators are used to form a truly random numerical sequence. In this paper, the possibility of creating promising generators of random numerical sequences of the second type, based on silicon photo-electronic multipliers with p - p-n - and n - n-p -structures by applying the pulsed optical radiation to these photo-detectors, has been shown. Using the experimental setup the influence of the supply voltage, optical radiation parameters, and, also, the parameters of the recording equipment, has been evaluated. The recommendations for choosing the values of the energy exposure of optical pulses, the overvoltage and the amplitude selection threshold, the implementation of which ensures that the generated random numerical sequence complies with the NST (National Institute of Standards and Technology) standard, have been formulated.
- Counter: 934 | Comments : 0
For detecting the low-intensity optical radiation the silicon photoelectronic multiplyers are used more often. However, not all characteristics of these photoelectronic multiplyers have been thoroughly studied. So, there is no information about the influence of supply voltage on the value of the dynamic range. In the work as the study objects, the test specimens Si-PEM with a p - p - n structure, produced by JSC Integral (Republik of Belarus), have been used, as well as the serially produced silicon photomultiplyers Ketek PM 3325 and ON Semi FC 30035. It has been found that an increase in the supply voltage leads to the critical decrease. It has been discovered that an increase an in the supply voltage leads to a decreased value of the threshold intensity. It has been proved that the dependence of the dynamic range on the supply voltage has a maximum. To ensure the maximum dynamic range of registration in the photo-detector devices based on the Si-photomultiplier tubes, it is necessary to select the photo-detector supply voltage, corresponding to this maximum. The results obtained in this article can be applied in the development and design of the devices for recording the optical radiation based on silicon photomultiplier tubes.
- Counter: 700 | Comments : 0
The implementation of such technology of data transmission as Li-Fi requires photodetectors that are optically sensitive in the visible range of wavelengths. The photomultiplier tubes are characterized by highest sensibility in this wavelength range, but also by large size, higher power supply voltage, and frangibility. An alternative to the mentioned type of photodetectors is a silicon photomultiplier tube (Si-PMT) characterized by good sensibility in the visible range of wavelengths. In this work, the throughput of an optical communication channel with an information receiver in the form of a Si-PMT is investigated. As a result, it was found that the highest throughput value corresponded to the supply voltage value equal to the breakdown voltage of the Si-PMT, and to the optical radiation wavelengths of 470 nm. It has been established that an increase in temperature causes a decrease in the transmission capacity of the photodetector, and an increase in the optical pulses’ radiant exposure leads to an increase in the transmission capacity. The results obtained can be used in the development of optical communication systems.
- Counter: 507 | Comments : 0
The influence of such important factors as supply voltage and temperature on the photo response characteristics of silicon photo-electronic multipliers has been insufficiently studied. In the work, the influence of theses factors on the temporal characteristics of the photo response of the silicon photo-electronic multipliers has been investigated. A block diagram of experimental setup has been presented, in which the source of optic radiation is light diode and the registration of the photo responses has been provided by specialized hardware-software complex, has been provided. The results of the study on the influence of supply voltage and temperature on kinetics and amplitude of the photo response of silicon photo-electronic multipliers, performed on n - n - p - and p - p - n -structures with pulsed excitation by light at a wavelength of 630 nm, have been presented. It has been stated that when exposed with optical pulses of the same duration, wavelength and energy exposure on the silicon photo-electronic multipliers at the same temperature and with the same overvoltage, the duration of the photo response is longer for silicon photo-electronic multipliers with p - p - n -structure. Duration of the rising edge has been associated with the gain ratio of photoinduced current and duration of the relaxation zone of the photo signal pulse has been associated with a value of the series resistance for silicon photo-electronic multipliers. The duration of the rise front is longer for silicon photo-electronic multipliers with a higher photo current gain factor. The silicon photo-electronic multipliers with a higher value of series resistance have a longer decline.
- Counter: 1268 | Comments : 0