SYNCHROINFO 2018 Systems of Signal Synchronization, Generating and Processing in Telecommunications, IEEE Conference # 43613
The international scientific and engineering conference “Systems of Signal Synchronization, Generating and Processing in Telecommunications” has been held since 1974. For 44 years of work the conference has become a widely known forum for specialists of the field.
The papers which are discussed at the conference can be divided into the following chapters:
– Synchronization Systems and Devices;
– Signal Generating and Shaping Devices;
– Signal Processing Devices.
The chapters content is concerned with fundamental problems of signal synchronization, generating and processing in the field of communications, broadcasting, radar, radio guidance and radio control. The questions of the practical issues are also including.
The presentations are made by the scientists and developers from 10 countries: Belarus, Azerbaijan, Germany, Kazakhstan, China, Lebanon, Mongolia, Russia, Uzbekistan and Ukraine.
The scientific paper is dedicated to the investigation of a rectangular waveguide R32 type with magnetic wall of mushroom-shaped metamaterial supplemented by a dielectric substrate. The computer model of the waveguide filter under consideration and its quantitative characteristics of S-parameters and voltage standing wave ratio received are presented. All collected data are appropriately organized in terms of convenience to compare the figures and submitted as the frequency dependence plots which are more representative and straightforward for analysis. Based on the results obtained it is possible to make assumptions about the qualitative transformation of waveguide properties under the influence of a mushroom-shaped metamaterial and prospects for a future integration this construction in the microwave devices. This groundbreaking treatment could be an underlying solution to the problem of miniaturization and performance in the modern technology development.The scientific paper is dedicated to the investigation of a rectangular waveguide R32 type with magnetic wall of mushroom-shaped metamaterial supplemented by a dielectric substrate. The computer model of the waveguide filter under consideration and its quantitative characteristics of S-parameters and voltage standing wave ratio received are presented. All collected data are appropriately organized in terms of convenience to compare the figures and submitted as the frequency dependence plots which are more representative and straightforward for analysis. Based on the results obtained it is possible to make assumptions about the qualitative transformation of waveguide properties under the influence of a mushroom-shaped metamaterial and prospects for a future integration this construction in the microwave devices. This groundbreaking treatment could be an underlying solution to the problem of miniaturization and performance in the modern technology development.
The purpose of this paper is to investigate the performance of the protocol of interaction between the reader and the tags. The subject of the work is automatic vehicle identification system (AVI) making use of passive ultra-high frequency radio frequency identification (UHF RFID) under EPC Class 1 Generation 2 protocol. In the thesis, protocol specifications that affect the probability of successful identification are considered and a simulation model of the communication protocol between RFID tags and the reader is given. The purpose of the thesis is the analysis and modeling of the radio frequency identification protocol standard EPC Class 1 Generation 2. During the diploma work, the EPC Class 1 Generation 2 standard was studied, which describes the technology of passive radio frequency identification, in particular, the communication protocol between tags with the reader, the anticollisional procedure for interrogating tags, access to various areas of tag memory, the reader's operating parameters, security issues. To simplify the description and logical separation of the functional presented in the standard, two levels are introduced: physical and logical. The description of these levels is given in the thesis. For the performance analysis, a model of a radio frequency identification system in Python 3 was developed. The software allows to simulate the procedure of interrogating tags and build and analyze the dependencies of the number of successfully read tags on the settings of the reader based on the model described above.
This paper is a continuation of the author’s previous study on methods of velocity measurements of navigation receivers and devoted to their comparative analysis.
Each method of measuring velocity has a few parameters. Let us fix all parameters except for one (main) and vary this parameter. The value of each varied parameter corresponds to some noise error of velocity measurements which can be characterized by standard deviation, or SD (cm/s). A dynamic model of GNSS receiver motion determines dynamic errors. Maximal dynamic error (MDE) (cm/s) is of interest in this case. This error depends on “maneuver phase”, i.e., a shift of the maneuver start time from the starting point of PLL control period and also the starting point of the secondary processing period. The maximal value of MDE is of interest in these shifts.
So, for each value of the varied parameter there is a pair of numbers: SD and MDE. Let us arrange these numbers in plane of the coordinate system: x-axis is MDE, and y-axis is SD. Connect nearest points and obtain a curve which is called an exchange diagram. Since SD and MDE vary within a wide range, the diagrams should be built in logarithmic scale, that is in dB relative to 1 cm/s. Let us call them logarithmic exchange diagrams (LED). Different LED were plotted for tough and soft dynamic scenarios for different methods of velocity measurements including the conventional one frequently discussed in the literature.
As a result of the analysis, a method of generating frequency estimates of the input signal and their further filtering using an after-satellite second order tracking filter, and a method based on quasi-optimal estimates of the input signal phase and further after-satellite filtration using the third order tracking filter have been recommended for tougher dynamic conditions. Under more favorable conditions in addition to the two above, a method of generating coordinate increments over one period with further after-coordinate filtration using the second order tracking filter, and a method of generating local coordinates with further aftercoordinate filtration using the third order tracking filter have been also recommended. In conclusion, a law of velocity estimate SD variation for one of the best recommended methods was investigated in the process of varying method parameters.
Measurements of velocity in navigation receivers are performed in two stages. At the primary (after-satellite) processing stage each of received signals is synchronized using a separate PLL, after that an estimation block (EB) estimates nonenergy (phase and frequency) and energy (SNR) parameters of the received signal. Doppler primary estimations can be subject to after-satellite filtration to obtain secondary frequency estimates. A number of Doppler estimates are conversed into primary estimates of velocity vector projections (for example, onto axes of the local Cartesian coordinate system) using the least square method (LSM). Primary estimates of velocity can be filtered at the secondary (after-coordinate) processing. Secondary velocity vector coordinates are outputted to users.
The present paper considers different methods of measuring velocity, they being different from each other by different tracking filters of primary and secondary processing and different EB. Primary filters operate at the same control frequency Fc as PLL (for instance, at Fc= 200 Hz), and LSM and secondary filters – at lower frequency FE < Fc (for example, at FE=100 Hz or FE=10 Hz). To shift from Fc to FE, some samples are rejected (intermediate samples are thrown). EB generates either primary estimates of instantaneous frequency or instantaneous phase of the input signal, or primary estimates of average input phase over control period Tc=Fc^-1. These primary estimates are fed to the filters of primary processing. At the outputs of these filters either secondary estimates of instantaneous frequency or estimates of averaged frequency and it’s derivative over period Tc are outputted which further are recalculated in estimates of instantaneous frequency. Based on thinned instantaneous phase estimates sometimes there are generated increments of these phase estimates over period TE = FE^-1. Primary estimates of either coordinates of the instantaneous velocity vector or averaged over period TE are fed to the input of secondary processing filters. In the first case, secondary estimates of instantaneous coordinates of the velocity vector are obtained at filter outputs at once. In the second case, at the filter outputs there are estimates of averaged velocities and accelerations over period TE which are further calculated in estimates of instantaneous velocity vector coordinates.
It has been shown that frequency estimation typically used in analog systems brings about a biased frequency (and hence, velocity) estimate when a receiver with digital PLLs has constant non-zero acceleration. Various algorithms of non-biased estimation have been also considered.