Proceedings of the Seventh International Conference on Telecommunications and Remote Sensing最新文献

{"title":"A GHz-MIMO perspective of shielded multi-wire transmission lines using proximity effect analysis","authors":"Janosch Ortmann, H. Bessai","doi":"10.1145/3278161.3278163","DOIUrl":"https://doi.org/10.1145/3278161.3278163","url":null,"abstract":"Transmission lines are basically described by their per-unit-length parameters. The computation of these parameters is a critical system design step. To get a precise model of transmission line behavior above 1 GHz, geometry and material constants must be taken into account. Also, coupling of electromagnetic waves (proximity effect) has to be considered. Proximity effect computation tends to be numerically unstable in the high frequency regions of interest. To solve this problem, a numerically stable solution will be presented using asymptotic behavior of modified Bessel functions. The calculation of an eight-conductor shielded transmission line parameter set is shown as an example.","PeriodicalId":409637,"journal":{"name":"Proceedings of the Seventh International Conference on Telecommunications and Remote Sensing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122484663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of TEC to determine foF2: differences and similarities at high and low latitudes","authors":"O. Maltseva","doi":"10.1145/3278161.3278172","DOIUrl":"https://doi.org/10.1145/3278161.3278172","url":null,"abstract":"The total electron content TEC finds wide application in various scientific and technological areas. One of applications is the use of TEC to obtain critical frequencies foF2 of the ionosphere. The most studied is the situation in middle latitudes. High and low latitudes are considered as problematic zones. In the present work, the situation in high and low latitudes is investigated, including at comparison with results in middle latitudes. Possibility of the TEC use to obtain foF2 is connected with their high correlation however in details this correlation was not investigated. In the present work, on an example of three stations of the American zone (Thule, Millstone Hill, Puerto Rico), latitudinal section of the northern hemisphere on a meridian 75°W it is shown, that: 1) correlation coefficients p(TEC, foF2) between foF2 and TEC lay in a range 0.7-1.0 in a seasonal course and 0.6-0.85 in a daily course with the least values for the station Thule. 2. The most clear seasonal dependence is related to that in the winter (January, December) correlation is worse, in an equinox (March, September) is better. 3. There is a tendency to higher correlation and smaller scatter of values in years of high solar activity, than in low activity. 4. Correlation coefficients ρ(δTEC, δfoF2) of deviations between δTEC and δfoF2 lay in the same range, as coefficients for magnitudes, and not strongly worsen during the disturbed periods, the least values here are at the station Puerto Rico. Estimation of a dependence ρ(δTEC, δfoF2) from indexes Kp and Dst and its approximations by a polynomial with degree n has shown, that: 1) degree of polynomial approximation and the best index of correlation depend on latitude (for high-latitude stations the greatest correlation is observed with index Kp, for middle - and low-latitude stations correlation with Dst can prevail). 2. Degree and the best index of correlation depend on a season (the greatest correlation is observed in winter months for high-latitude stations and in the summer for low-latitude stations). 3. Degree n=3 is insufficient for approximation, often degree of reliability R^2 for n=4-6 exceeds reliability for n=3 twice. 4. Reliability degree can exceed the level 0.5 testifying strong dependence and possibility of the forecast of parameters. As a whole, differences between high and low latitudes consist in a difference of coefficients of correlation, similarities - in possibility of the TEC use to obtain foF2 practically at all latitudes, i.e., details of behavior of TEC can differ, but the main result is identical: the use of TEC allows to improve conformity of the calculated values of foF2 to experimental data in 1.5-2.5 times. Residual deviations do not exceed 10 %.","PeriodicalId":409637,"journal":{"name":"Proceedings of the Seventh International Conference on Telecommunications and Remote Sensing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128401837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Matched loading for calibration of passive matrix millimeter wave imaging system","authors":"Hao Liu, Xinyu Yin, Hao Li, J. Qiu, Hongjun Chu, Alexander Denisov","doi":"10.1145/3278161.3278169","DOIUrl":"https://doi.org/10.1145/3278161.3278169","url":null,"abstract":"Passive microwave imaging system are widely designed for the remote sensing, radio-astronomical observation and especially for the detection of weapons and contraband concealed on persons under clothing in the special control devices for public security. This system must have various special calibration at the used temperatures. There described in technical details simple square matched loading for the calibration matrix radiometric 8 mm receiving array which has VSWR not pure than 1,10.","PeriodicalId":409637,"journal":{"name":"Proceedings of the Seventh International Conference on Telecommunications and Remote Sensing","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133694934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Convolutional codes with different constraint lengths and their application in DVB-S","authors":"L. Laskov","doi":"10.1145/3278161.3278165","DOIUrl":"https://doi.org/10.1145/3278161.3278165","url":null,"abstract":"This paper presents a study and results from the effectiveness of the convolutional codes with code rate 1/2 and constrained lengths 7, 8 and 9. The dependencies of the bit error probability at the output of the Viterbi decoder from the generator polynomials have been studied. The obtained most efficient codes and their basic parameters are given. The dependences of the BER at the output of the Viterbi decoder from the Eb/No ratio at the receiver input for these codes have been studied. An analysis of the possibilities for increasing radio channel noise immunity when using concatenated coding with Reed-Solomon and newly proposed convolutional codes instead of the codes used in the DVB-S standard is performed.","PeriodicalId":409637,"journal":{"name":"Proceedings of the Seventh International Conference on Telecommunications and Remote Sensing","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122885509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An algorithm for synthesis of generalized gordon-mils-welch signals","authors":"M. Iliev, B. Bedzhev, I. Tsvetkova, Plamen Yanakiev","doi":"10.1145/3278161.3278162","DOIUrl":"https://doi.org/10.1145/3278161.3278162","url":null,"abstract":"The radio signals possessing both good correlation properties and high structural complexity provide steady operation of wireless communication systems in hostile radio - electronic environment. With regard to this fact, in the paper we propose a new algorithm for synthesis of complex phase manipulated signals, possessing both good correlation properties and high structural complexity. Its advantages are: effectiveness from computational point of view and diminishing the losses in the signal-to-noise ratio, caused by the processing with side-lobe suppression filters.","PeriodicalId":409637,"journal":{"name":"Proceedings of the Seventh International Conference on Telecommunications and Remote Sensing","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126919389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mobile devices: effect on human health","authors":"Magdalena Garvanova, B. Shishkov, Stoyan Vladimirov","doi":"10.1145/3278161.3278176","DOIUrl":"https://doi.org/10.1145/3278161.3278176","url":null,"abstract":"Currently mobile devices are of essential benefit for people in their personal and business activities. It is hence worthwhile maximizing those benefits and this in turn includes (among other things) minimizing corresponding health threatening effects that mainly concern the cell phone electromagnetic waves - this is the focus of the current paper. In particular, we are considering different GSM devices, analyzing the electromagnetic waves accordingly, focusing especially on the human body thermal effect - how the body temperature changes in the course of cell phone conversations of different duration. This is considered indicative with regard to the electromagnetic fields that are claimed to affect negatively not only the human body as a whole but also particular body organs. Further, the effect of using cell phones is claimed to go also beyond the mentioned physical \"dimension\", affecting people psychologically since being \"with\" the cell phone turns out to be kind of \"addiction\" with millions of users. Hence, the paper raises awareness (supported by experimental results) with regard to those worrying effects and draws recommendations accordingly.","PeriodicalId":409637,"journal":{"name":"Proceedings of the Seventh International Conference on Telecommunications and Remote Sensing","volume":"177 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115585118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}