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1、Measurements of background electromagnetic fields in human environment 人類環(huán)境背景電磁場的測量T. Trcek1, 3, B. Valic2, 3 and P. Gajsek3T. trcek1、 3、B 3和gajsek3 valic2,P.1 University of Ljubljana/Faculty of Electrical Engineering, Ljubljana, Slovenia1盧布爾雅那大學(xué)電氣工程學(xué)院,盧布爾雅那,斯洛文尼亞2E-NET Okolje, Ljubljana, Slovenia2e
2、-net okolje,盧布爾雅那,斯洛文尼亞3Institute of Non-ionizing Radiation, Ljubljana, Slovenia 非電離輻射,盧布爾雅那研究所,斯洛文尼亞Abstract An extensive measurement campaign was car-ried in Slovenia to evaluate background electromagnetic field intensity in different living environments. As electromagnetic field meter personal ex
3、posure meter Antennessa DSP 090 with analysis software for data processing and analysis was up-graded with commercial GPS receiver and custom made data logger unit to save geographical data of the measurements.摘要:廣泛的測量活動進行評估的背景下,斯洛文尼亞的電磁場強度在不同的生活環(huán)境。作為電磁場計的個人曝光計090 antennessaDSP進行數(shù)據(jù)處理與分析軟件分析了不同商用GPS接
4、收機和定制數(shù)據(jù)記錄器單元保存地理數(shù)據(jù)的方法概述。Using this measuring system, mounted on a car roof or bici-cle, eight locations across Slovenia were measured: cities Ljubljana and Maribor, part of city Kranj, part of city Koper with nearby villages Labor, Hrvatini and Tinjan and village ?elje near Ilirska Bistrica. The mea
5、sured frequency spectrum was limited to GSM, DCS, UMTS, FM and TV signals.使用該測量系統(tǒng),安裝在車頂或自行車,斯洛文尼亞各地的八個地點進行了測量:城市盧布爾雅那和馬里博爾市克拉尼部分城市科佩爾和附近村莊的一部分勞動,hrvatini 和tinjanelje伊利爾斯卡比斯特里察附近村? 。測得的頻譜是有限的GSM ,DCS,UMTS , FM和TV 信號。From the results it is clear that typical electromagnetic field exposure is low. Maxi
6、mum values merely reach 3 % of refer-ence levels for I. region of Slovenian legislation, which is 0,3 % of ICNIRP reference levels for general public. The only excep-tion is Tinjan, where radio tower is located. Measurements done in the vicinity of this radio tower exceeded 5 V/m, which is upper det
7、ection limit of measuring system.從結(jié)果很顯然,典型的電磁場暴露是低。最大值僅僅達到 3% 的參考水平,即斯洛文尼亞立法的地區(qū),這是 0.3% ICNIRPR一般公共參考水平。唯一的例外是 tinjan,無線電塔位于。在這座無線電大樓附近做的測量超過 5伏/米,這是上限檢測限測量系統(tǒng)。The results of this measurement campaign will be presented on interactive map, open to general public through internet, where everyone will b
8、e able to obtain the measured values of every single measurement.這個測量活動的結(jié)果將在互動地圖,通過互聯(lián)網(wǎng)面向公眾,人人都能得到的每一個測量的測量值管理。Keywords Antennessa DSP 090, Electromagnetic fields, 關(guān)鍵詞: antennessa DSP 090,電磁場,Dosimetry劑量學(xué)INTRODUCTION一、引言In modern lifestyle we are exposed to many different en-vironmental factors: phys
9、ical, chemical and biological fac-tors from environment, which have great impact on our quality of life. At the same time public wants to have the information about quality of living environments. Both these factors stimulate different measurement campaign, inbetween also of background electromagnet
10、ic fields.在現(xiàn)代的生活方式,我們接觸到許多不同的環(huán)境因素:物理、化學(xué)和生物的環(huán)境因素,這對我們的生活質(zhì)量影響很大。同時,我公眾想要有關(guān)于生活環(huán)境質(zhì)量的信息。這些因素都刺激不同的測量活動,同時背景電磁場之間。Measuring background electromagnetic field (EMF) is an effective way to determine the overall exposure of general public to EMF. At the Institute for Non-ionizing radiation we used personal do
11、simeter with commercial name Anten-nessa DSP 090 for this purpose 1. It is an example of selective instrument for measuring personal exposure to EMF through a longer time period. To expand the function-ality of the personal dosimeter we connected it to the cus-測量背景電磁場(電動勢)是確定一般公眾對電動勢的整體接觸的有效途徑。在非電離輻
12、射所采用的個人劑量計商業(yè)名稱天線 N essa DSP這一目的 090 1 。這是一個選擇性的儀器測量個人暴露于電磁場通過較長時間的例子。擴展的功能下 Y的個人劑量計我們連接到客戶 223測量背景電磁場(電動勢)是確定一般公眾對電動勢的整體接觸的有效途徑。在非電離輻射所采用的個人劑量計商業(yè)名稱天線 N essa DSP這一目的 090 1 。這是一個選擇性的儀器測量個人暴露于電磁場通過較長時間的例子。擴展的功能下 Y的個人劑量計我們連接到客戶 測量背景電磁場(電動勢)是確定一般公眾對電動勢的整體接觸的有效途徑。在非電離輻射所采用的個人劑量計商業(yè)名稱天線 N essa DSP這一目的 090 1
13、 。這是一個選擇性的儀器測量個人暴露于電磁場通過較長時間的例子。擴展的功能下 Y的個人劑量計我們連接到客戶 -tom made data logger with GPS receiver. It allowed us to measure background EMF in human environment to deter-mine the real exposure of general public to EMF in different living environments in Slovenia.湯姆與 GPS接收機的數(shù)據(jù)記錄器。它允許我們衡量人的環(huán)境背景電勢確定公眾電磁場暴露的
14、真正不同的生存環(huán)境在邋遢IA 。Final goal of this research was to represent measurements as an array of points on an interactive map. The color of the points is an indicator of the real value of measured EMF, which is obtained by clicking on the point. In the future, the results will be available on internet.本研究的最
15、終目標(biāo)是代表測量的一個數(shù)組的互動地圖上的點。點的顏色是一個指標(biāo)的實際值的測量電動勢,這是通過舔點。在未來,結(jié)果將可在互聯(lián)網(wǎng)上。MATERIALS AND METHODS II 。材料與方法For EMF measuring specific measuring systems and methods are needed. One of such systems for selective EMF exposure measurement is Antennessa DSP 090. Figure 1 shows selective EMF measurement with Antenness
16、a DSP 090, where contribution for each component of the EMF spectrum is shown.對于電動勢測量特定的測量系統(tǒng)和方法是必要的。一種選擇性的電磁場暴露測量系統(tǒng)是 antennessa DSP090。圖 1顯示了選擇性的電動勢測量與螞蟻ennessa DSP090,其中的每個組件的貢獻是證明電磁頻譜。Personal exposure meter used as a measurement sys-tem for measuring background of EMF in human envi-ronment needs
17、to be upgraded with GPS module and data logger unit to save the geographical coordinates of the measurements. Whole measurement system includes dosimeter Antennessa DSP 090, commercial GPS receiv-ing module and custom made loggermodule used for GPS data storing and managing GPS module. Part of measu
18、rement system is also software installed on per-sonal computer, handling measured data. All system components are shown in figure 2.個人暴露量表作為測量系統(tǒng)用于測量電動勢在人類環(huán)境背景需要升級與 GPS模塊和數(shù)據(jù)記錄器單元保存的地理坐標(biāo)測量系統(tǒng)。整個測量系統(tǒng)包括劑量計 antennessa DSP090,商用 GPS接收模塊和定制的用于 GPS數(shù)據(jù)存儲和管理的 GP S模塊采集模塊。測量系統(tǒng)的一部分也安裝在個人計算機軟件處理測量數(shù)據(jù)。所有系統(tǒng)組件如圖2所示。Fig
19、ure 1: Selective EMF measurement with DSP 090 圖090:數(shù)字信號處理器的選擇性電動勢測量 1T. Jarm, P. Kramar, A. ?upani? (Eds.): Medicon 2007, IFMBE Proceedings 16, pp. 222225, 2007 ? Springer-Verlag Berlin Heidelberg 2007T. Jarm , P.Kramar , A.?upani?(主編):介質(zhì) 2007、國際訴訟 16,pp.222225、 2007?施普林格出版社柏林海德堡2007Measurements of
20、background electromagnetic fields in human environmentA. Antennessa DSP 090Antennessa DSP 090 is personal exposure meter for per-sonal EMF. Measurement is focused on FM, TV and wire-less communications as mobile phones and their base sta-tions. These signals are main players and contribute the major
21、 part of EMF in urban environment. Measurement is selective within each frequency band. Main characteristics of Antennessa DSPare: antennessa DSP090個人曝光表為個人的電動勢。測量的重點是調(diào)頻、電視和無線通訊手機及其基站。這些信號是主要的球員在城市環(huán)境中貢獻的主要部分。測量是在每個頻率波段選擇性。antennessa DSP的 090個主要特征:registering EM signal 24 hour per day in adjustable i
22、ntervals;注冊電磁信號24小時,每天可調(diào)時間間隔;insensibility to interferences with user activity;麻木與用戶活動的干擾;40dB dynamic range with sensitivity 0,05-5V/m;敏感性 0,05-5v / M 40dB 動態(tài)范圍;isotropy;各向同性;FM, TV, GSM, DCS and UMTS frequency range;調(diào)頻、電視、GSM 、 DCS 和 UMTS 頻率范圍;distinction between base and subscriber station;基站和用戶站
23、之間的區(qū)別;adjustable sampling interval from 3 to 255 seconds;可調(diào)采樣間隔從3秒到 255秒;memory autonomy for 7000 measurement records;7000 測量記錄的記憶自主權(quán);few days battery autonomy;幾天電池自主權(quán);small size and weight (450g).體積小、重量輕(450g)。B. GPS moduleB. GPS 模塊GPS model consists from two parts. First part is a com-mercial GPS
24、receiving module for receiving satellite signal and determining geographical coordinates. Second part is data logging and managing unit, used for mange GPS receiv-ing module and logging GPS data. This unit was developed according to our requirements. Our basic requirements were:全球定位系統(tǒng)模型由 2部分組成。第一部分是
25、一個商業(yè) GPS接收模塊接收衛(wèi)星信號,確定地理坐標(biāo)。第二部分是數(shù)據(jù)記錄和管理它用于處理 GPS接收模塊和日志記錄的 GPS數(shù)據(jù)。這個單位是根據(jù)我們的要求開發(fā)的。我們的基本要求是:memory autonomy comparable to DSP 090;記憶自主權(quán)與數(shù)字信號處理器090;data should be stored permanently (flash card);數(shù)據(jù)應(yīng)永久保存(閃存卡);battery autonomy comparable to DSP 090;電池自主權(quán)與數(shù)字信號處理器090;Figure 2: Measurement system圖 2:測量系統(tǒng)Cons
26、idering all mentioned criterion we chosen following places for our measurement: Ljubljana, Maribor, part of Kranj,part of Koper with nearby villages: Labor, Hrvatini and Tinjan and ?elje near Ilirska Bistrica.考慮上述準則,我們選擇了以下為我們測量的地方:盧布爾雅那、馬里博爾、部分語與附近村莊科佩爾部分:勞動hrvatini 和 tinjan 和 ? 附近 elje 伊犁 RSKA 比斯特
27、里察。The most part of measurements was realized by car with measurement system mounted on roof carriers. Some parts of Ljubljana with prohibited car traffic were measured by bicycle.測量系統(tǒng)中最重要的部分是在屋頂?shù)妮d體上安裝測量系統(tǒng)。盧布爾雅那市部分地區(qū)禁止汽車交通量進行自行車測量。During measurements occasional transfer of recorded data to computer
28、was necessary due to the safety reasons. Data from dosimeter are written in a .mes format recognized by Antennessa software. Software allows exporting data to standard MS Excel format. Coordinates from data logger在測量過程中偶爾的記錄數(shù)據(jù)傳輸?shù)接嬎銠C是必要的,由于安全原因。數(shù)據(jù)從劑量計用。 MES 格式 antennessa軟件識別。軟件重新允許導(dǎo)出數(shù)據(jù)以標(biāo)準格式的格式。從數(shù)據(jù)采集器
29、的坐標(biāo)geographical coordinates from GPS should be conver- unit are stored in .txt format and must be combined with 地理坐標(biāo)的 GPS應(yīng)該收斂單元存儲在 txt 格式,必須結(jié)合ted to Gauss-Krueger coordinates;泰德高斯克魯格坐標(biāo);DSOP 090 LED synchronization pulse should be used to trigger pulse for data logging; 090個 LED 同步脈沖 DSOP應(yīng)用于觸發(fā)數(shù)據(jù)記錄脈沖;
30、supported connectivity with PC.支持與 PC的連接。C. Measurements and data processing測量和數(shù)據(jù)處理Prior to starting measurements the locations for meas-urements were defined. To obtain representative sample it is necessary to cover enough population as well as to include different living environments and EMF sourc
31、es. Including large cities we included enough population and different EMF sources. But measurements in cities only are not rep-resentative enough and rural areas should be included too. In rural areas it is appropriate to include areas with at least one strong source of EMF.開始測量,確定了測量的位置之前。為了獲得代表性的
32、樣品需要足夠的人群以及不同的生活環(huán)境,包括蓋 NTS 和電動勢源。包括大城市,我們有足夠的人口和不同的電動勢源。但測量城市只不代表足夠的農(nóng)村應(yīng)包括 TOO 。在農(nóng)村地區(qū),它是適當(dāng)?shù)模ㄖ辽儆幸粋€強大的電動勢源區(qū)。Excel data after transfer to computer.Excel 數(shù)據(jù)傳輸?shù)诫娔X后。After combining, data without pairs value-coordinate were eliminated. It was also necessary to filter all measure-ments that are too close.
33、We decided to filter out all meas-urements that are less then 20 meters apart. Program code for filtering was done by MS Visual Basic. It first calculates distance from one measurement to each other and then eliminates all measurements that are closer then 20 meters to comparable measurement. In pri
34、nciple each measurement has to becompared to each measurement, therefore number of comparisons rises with the square of measurements.20米外。結(jié)合后,消除了數(shù)據(jù)沒有對值坐標(biāo)。同時也需要過濾,太接近的所有措施。我們決定過濾出所有測量都少程序代碼進行過濾是由微軟的視覺基本。它首先計算距離從一個測量,然后消除所有測量,是接近20可比測量儀表。在原則上,每一個測量都必須與每一個測量值相比較,因此,比較的數(shù)量與測量的平方的平方。For instance, in Ljubl
35、jana where more then 12000 meas-urements were acquired, 144 million of comparisons are needed.Calculation time was approximately half an hour. After filtering, measurement points were drawn into graph for fast survey.For Ljubljana, graph is shown in figure 3.例如,在盧布爾雅那,超過12000測量獲得,1億 4400 萬的比較是必要的。計算
36、時間約為半小時。濾波后測量點圖為快速調(diào)查。對于盧布爾雅那,圖如圖3所示。_ IFMBE Proceedings Vol. 16_224T. Trcek, B. Valic and P. Gajsek10600010400010200010000098000458000460000462000464000466000468000Figure 3: Graphically presented filtered measurement pointsThe accuracy of filtered measurement points was verifiedon The EnvironmentalA
37、gency,Ministryof the Environ-ment and Spatial Planningof the Republicof Slovenia.Coordinates obtained from GPS device always have somedeviation, whichis normallyless than 1 m. In the case ofinappropriate positionof visiblesatellites deviation arises.Several measured pointswithobviouslywrongpositionw
38、ere displaced to the most credible position;those withdoubtful positionwere deleted. An example of filtered andcorrected measurements is shown in figure 4.他過濾的精度測量點在環(huán)境機構(gòu)驗證的環(huán)境和空間規(guī)劃部斯洛文尼亞共和國。從全球定位系統(tǒng)獲得的坐標(biāo)總是有一些偏差,通常不到1米。在不適當(dāng)?shù)奈恢玫那闆r下,可見衛(wèi)星出現(xiàn)偏差。幾個測量點,顯然是錯誤的位置用最可靠的位置;那些可疑的位置被刪除。如圖4所示,一個濾波和校正測量的例子。When multip
39、le frequency and/or source exposure is pre-sent Slovenian legislation2 directs that all measurementresults must be converted from V/m to percent of maximumvalues defined. Safety index SI is calculated using equation:當(dāng)多個頻率和/ 或暴露源是預(yù)先給斯洛文尼亞立法 2 指示,所有測量結(jié)果必須從伏/米轉(zhuǎn)換成最大值定義。安全指數(shù)用方程計算:Figure 4: Measurement po
40、ints represented on map2(1)SI= (Ei /Emi ) ,_ IFMBE Proceedings Vol. 16_Measurements of background electromagnetic fields in human environment225where SI is safety index in percents, Ei is measured value of frequency component and Emi is maximum allowed value of frequency component.其中 Si是百分比的安全指數(shù),EI
41、是頻率成分和EMI 測量值是頻率分量最大允許值。Maximum allowed value Emi is frequency dependent and has two values at each frequency. Slovenian legislationdifferentiates the area between I. region area and II. region area. II. region area is where normal EMF exposure is al-lowed and is the same as ICNIRP reference levels
42、for gen-eral public 3. I. region area is where safety isincreased, which means that allowed EMF exposure is decreased for factor 10. For measured frequency bands the values of Emi in V/m are shown in table 1.最大允許的值,電磁干擾是頻率依賴性的,并具有2個值在每個頻率。斯洛文尼亞立法 2 區(qū)分 I 區(qū)和 II 區(qū)之間。區(qū)域面積。II 。區(qū)域面積在正常的電磁場暴露允許和為代艾萊依公 3 IC
43、NIRP 參考水平相同。一、區(qū)域安全性提高,這意味著允許電動勢的曝光量減少10因素。對于測得的頻率波段的電磁干擾的值在伏/米顯示在表 1。RESULTS三、結(jié)果Measuring system consisting from Antennessa DSP 090, GPS receiving module and data logger was used to measure background EMF in human environment at 8 different locations across Slovenia. Totally almost 20000 measurement
44、s were captured. For each measurement fol-lowing data were stored: EMF value for six different fre-quency ranges, coordinates, date and time. After the filtra-tion (locations closer than 20 meters were excluded) 12059 measurements remained.從 090 antennessaDSP組成的測量系統(tǒng)、GPS接收模塊和數(shù)據(jù)記錄器是用來測量在8個不同的地點在斯洛文尼亞的
45、人文環(huán)境背景電磁場。幾乎完全20000測量被抓獲。對于每個測量以下數(shù)據(jù)存儲:電動勢值為六個不同的頻率范圍、坐標(biāo)、日期和時間。的過濾后(接近的地方20米之外) 12059測量仍然保持。For majority of locations the most important EMF source is GSM system with FM signals close. For Ljubljana maxi-mum GSM signal was measured in Ljubljana-Tomacevo, where electric field strength was 2.28 V/m, or
46、3.1 % of I. region area reference levels 2. Close to this was maximum FM signal, measured at Ljubljana Castle. Nearby there is radio diffusion system located and measured electric field strength was 1.57 V/m or 3.3 % of I. region area reference levels. Average values show that the most part of overa
47、ll EMF exposure is contributed by GSM system. In Ljubljana average value of GSM signal is 0.127 V/m, or merely 0.01% of I. region area referencelevel.FM 信號的 GSM 系統(tǒng)多數(shù)關(guān)閉。盧布爾雅那最大的GSM 信號是在盧布爾雅那 t對于位置最重要的電動勢源與omacevo測量,在電場強度為2.28伏 /米,或 3.1% 的一個區(qū)域的參考水平 2 。接近這是最大的調(diào)頻信號,測量在盧布爾雅那城堡。附近有無線電擴散系統(tǒng),并測得電場強度為1.57伏 /米
48、或 3.3%島地區(qū)的參考水平??傮w平均值表明,電磁場暴露大部分是由GSM 系統(tǒng)。在 GSM 信號的平均值,我的盧布爾雅那的0.127伏 /米,或僅 0.01%的一個區(qū)域參考水平。The results in Maribor are similar to those in Ljubljana. The value of maximum FM signal is 0.42 V/m or 0.42% of I. region area reference levels 2 and was measured nearby radio diffusion system in Tezno on Nikov
49、a street. In the frequency range of GSM signals two equivalent maximums在馬里博爾的結(jié)果是類似于那些在盧布爾雅那。最大調(diào)頻信號的值是0.42伏 /平方米或 0.42% 的區(qū)域參考水平 2 ,并在附近的無線電擴散系統(tǒng)測量ezno nikova 街上。在 GSM 信號的等效值的頻率范圍 T able 1: Maximumallowed value of EMF in V/mfrequencyareaI. region areaII. region areaFM8.627.5TV 38.627.5TV4&59.329.7GSM12
50、.941.1DCS18.258.1UMTS19.061.4were measured with values of 0.97 V/m, or 0.57% of I. region reference levels 2. First value was measured in Studenci, precisely on Valvasorjeva street near base station. Second value was also measured in Studenci near base station on Koresova street.測量值為 0.97伏 /米,或 0.57
51、% 的一個區(qū)域參考水平 2 。測量 studenci 是第一價值,正是在 valvasorjeva 街附近的基站。二值進行測量紅 studenci附近基站 koresova街。Like in Ljubljana, average values for Maribor show that GSM system is the greatest contributor. Average value of GSM signal in Maribor is 0.1 V/m, or 0.006% of I. area region reference levels. Other average value
52、s are at lower detection limit of measuring system (0.05 V/m) and are therefore not point of our interest.像在盧布爾雅那,在馬里博爾表明GSM 系統(tǒng)是最大的貢獻者的平均值。在馬里博爾GSM 信號的平均值為0.1伏 /米,或 0.006% 我區(qū)參考水平。另一個平均值在檢測系統(tǒng)的檢測下限(0.05伏 /米),因此不是我們的興趣點。IV. CONCLUSION四結(jié)論From the measurements it is clear that overall EMF expo-sure in human environment is low. Maximum values hardly riches 3% of I. region reference levels of Slovenian legislation 2, and are almost hundred times lower than allowed. Compar-ing results of different frequency r
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