The interim release of Pathloss version 5 is structured in the following options:PL5B – Basic program – point to point link designThe basic program consists of the network display and the automated linking and design features for point to point radio links. This includes the design sections for terrain data, antenna heights, diffraction, transmission analysis and reflections – multipath analysis. These features are common to all program options.PL5C – Point to multipoint design – local studiesThe point to multipoint design option adds multi-sectored base stations to the network display. These are used for the automatic PTMP linking and design features. Additionally local coverage studies can be carried out centered on a base station using signal strength, fade margin or visibility as the display criteria.PL5I – InterferenceThe interference option calculates the aggregate interfering level of all transmitters in a selected group. The subsequent receiver threshold degradation and increase in outage time is calculated for rain and multipath correlated fading.
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The analysis can be carried out for all radio types in point to point and point to multipoint networks taking into account the duplex arrangement on PTMP radios. Interference through passive repeaters is included in the calculation.PL5T – Interference, point to multipoint design, local and area studiesThis option combines the point to multipoint – local studies and interference options and adds area study analysis. In an area study, signals from a number of base stations are calculated into a common area. FCC EMISSION DESIGNATORSDetailed ListLast Rev.
1998WARC-79, the World Administrative Radio Conference that rewrote manyof the world's radio regulations, adopted a new system of emissionclassification. The traditional A (Amplitude), F (Frequency), and P(Pulse) was intuitive, but limited and clumsy when dealing with newmodes.The world's radio bodies, including the FCC, gradually phased in thenew system until today it completely replaces the old one.The formula for the new designations, loosely from ITU radioregulations 264 through 273, and Appendix 6, Part A, is:BBBBMNIDM,where means optional when writing emission specs.BBBB = Necessary Bandwidth (shown in FCC records, but is oftenomitted elsewhere)Uses a letter and three numbers.
Pathloss 5.0 Will released on February 2009Program optionsPathloss version 5 is available in several optionsPL5B – Basic program – point to point link designThe basic program consists of the network display and the automated linking and design features for point to point radio links. This includes the design sections for terrain data, antenna heights, diffraction, transmission analysis and reflections – multipath analysis.
These features are common to all program options.PL5C – Point to multipoint design – local studiesThe point to multipoint design option adds multi-sectored base stations to the network display. These are used for the automatic PTMP linking and design features. Additionally local coverage studies can be carried out from a base station using signal strength, fade margin or visibility as the display criteria. In addition to the Pathloss deterministic diffraction algorithms, local studies can be carried out using the F(50,50), F(50,90), F(50,10) curves, Okimura (Hata) and Cost (Hata) empirical algorithms.PL5I – InterferenceAn interference analysis can be carried out between groups of links in the network display or between a network display group and the Pathloss site database for all radio types. For each receiver, the aggregate interfering level of all transmitters is calculated. The receiver threshold degradation and the resulting increase in the outage probability is then determined taking into account the fade correlation for rain and multipath fades.
Net path loss (dB). Radio model 32 QAM 3-DS-3. 32 QAM 3-DS-3. TX power (watts). TX power (dBm).
Interference through passive repeaters is included in the calculation.PL5T – Interference, point to multipoint design, local and area studiesThis option combines the point to mulitpoint – local studies and interference options and adds area study analysis. In a local study each base station has its own coverage centered on the base station. In an area study, signals from a number of base stations are calculated into a common area. In addition to receive signal levels, an area study can display the most likely server, carrier to interference and simulcast delay.Program organizationAll operations are centered around the network display which provides a geographic layout of sites and links. The following backdrops are available in this display:. Geo-referenced imagery in bmp, png, jpg and tif file formats. The geo reference information can be obtained from external text files (Planet type), MapInfo tab files, directly from geo-tiff files or can be manually geo referenced directly in the program.
Vector data in ESRI shapefile or Planet formats. Elevation displays in a flat and shaded format. The elevation ranges, absolute- relative settings, colors, and transparency are completely configureable. A 3 dimensional elevation display showing the Fresnel zone radius on links. Pan, zoom and the view point control allow the user to effectively fly along a path. Clutter displays. The color legend and overall transparency are completely configureableThe Pathloss program contains two separate applications as follows.
PL50 – network display and integrated link design sections. PL50L – link design sections onlyIn the network display, the link design sections are accessed by clicking on the specific link. It is not possible to access the link design sections for a link which are not associated with the network display using the standard open file dialog. The stand-alone PL50L link design application is used for this purpose.Network display operationsOperations are based on groups or a selection of sites and links. A selection is a temporary group.
There can be any number of named groups and these can overlap other groups. Groups of links can be automatically created based on path length, frequency and fade margin The default group is all sites and links. The following operations are carried out in the network display. Interference calculations between two groups of links in either or both directions. One of the groups can be the Pathloss site database.
Automatic point to point linking – generate all possible links between two groups of sites and determine the final configuration based on path length, antenna heights, diffraction loss or fade margin. Automatic point to multipoint linking – generate links from a base station to a group of sites or all sites within a specified radius and determine the final configuration based on path length, antenna heights, diffraction loss or fade margin. Remote sites are linked to the best sector at the base station. Automatic link design – specify the equipment parameters and the design methods and algorithms for a group of links and generate path profiles and carry out a complete transmission analysis.
This feature is also used in the automatic point to point and point to multipoint linking. Point to point channel frequency and polarization assignments. Network performance analysis. Passive repeater design.
Local and area studies. Report generation for a group of links.
Any combination of report options can be printed for the selected groupExport file formatsThe network display can be exported in the file formats listed below. The 3D View command in Global Mapper allows registered users to view gridded elevation data and any overlying raster or vector data in a true perspective 3D manner. When selected, the 3D View command displays a window containing a 3D view of the data in the current Global Mapper view. Any imagery or vector data being drawn on top of the elevation grid(s) in the main Global Mapper view will automatically be draped on top of the elevation data in the 3D View window.The image below depicts a sample of the 3D View window displayed using 250K USGS DEM data for Salt Lake City, UT overlaid with DOQ satellite imagery from the TerraServer import command under the File menu. The 3D View window contains a toolbar with command buttons allowing you to modify the default view.
You can use the mouse to rotate the view around as well as zoom in. The arrow keys on the toolbar allow you to pan the data visible in the 3D view in any direction.
The zoom in and out buttons allow you to zoom in or out on the center of the 3D view. Additional buttons are also available for modifying the vertical exaggeration, displaying water, and saving the 3D view contents to a Windows BMP, TIFF, PNG, or JPG file. The contents of the 3D View window will always reflect what is visible in the main Global Mapper view. This means that as you pan and zoom around the main Global Mapper view, the contents of the 3D View window will pan and zoom around as well. The reverse is also true in that the pan and zoom buttons on the 3D View window will cause the main Global Mapper view to pan and zoom as well. Another example of the 3D view is displayed below.
This time, it is several 24K USGS DLGs for Blue Springs, MO overlaid on several 24K USGS DEMs for the same area. You can also save a measurement to a separate feature by right clicking and selecting “Save Measurement” from the list that pops up. You can then export these measurements to new vector files, such as Shapefiles or DXF, or modify them with the Digitizer Tool. There is also an option to copy the measurement text to the clipboard when you right-click. If you have gridded elevation data loaded under the measurement, you can also calculate the Cut-and-Fill volume either within the measurement area or within some distance of the measurement line. To do this,simply right click then select the “Measure Volume (Cut-and-Fill)” option that appears.
Selecting this option will display the Setup Volume Calculation Parameters dialog (pictured below), which allows you to set up thevolume measurement. The PathProfile/LOS command selects the 3D path profile/LOS (line of sight) tool as the current tool. This tool allows you to get a vertical profile along a user-specified path using loaded elevation datasets. In addition, registered users can perform line of sight calculations along the defined path.
To define the path along which to generate the 3D path profile, first select the path profile tool as your current tool. Press and release the left mouse button at the position where you wish to start the path. Move the mouseto the next position that you want to include in the path profile, then press the left mouse button again. Right click on the last location in the path profile to complete selecting points and display the Path Profile/Line of Sight dialog (pictured below).
The Path Profile/Line of Sight dialog will appear displaying the 3D path profile of the selected path. Any points along the path that did not have elevation data underneath will be treated as an elevation of zero. You can also generate 3D path profiles for existing line features by selecting the line feature in the Digitizer Tool, right clicking, then selecting the Generate Path Profile From Line option on the menu that is displayed. The Path Profile/Line of Sight dialog displays the 3D path profile and provides several options related to the profile.
A vertical scale is displayed on the left hand side of the profile window. The start and end coordinates of the path are displayed at the top of the profile window. If more than two points are in the path, the intermediate points will be marked in the profile window with a yellow dot.
These intermediate points can be toggled on and off using an option available by right clicking on the path profile window. Also note that this dialog is resizable.
Right clicking on the profile window brings up an options menu allowing the user to change the start and end positions, select the units (meters or feet) to display the elevations in, configure display of the path profile, and display a dialog containing details about the path. These options are also available under the Options menu on the dialog. The File menu contains options allowing you to save the path profile/line of sight data to a file. The individual options are described below.
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The Save To Bitmap option allows registered users to save the contents of the path profile window to aWindows bitmap (BMP) file for use in other applications.Need This Software?? Contact USNote: Need Pathloss 4.0?? Pathloss 4.0 Full Version?? Pathloss with coverage?? Pathloss 4.0 with interference?? Pathloss 4.0 with background network??
Path loss 4.0??TEms 6 or 8?? Global Mapper 10?? Contact me on [email protected] or +028.
Sistem yang multiple access (MA) adalah sistem yang dapat melayani banyak pelanggan (user) secara bersama-sama (simultan). Agar terjadi multiple access, maka harus tersedia kanal-kanal/saluran-saluran yang jumlahnya lebih dari satu. Jika pada saat yang sama terdapat 10 pelanggan yang ingin dilayani, maka diperlukan kanal sebanyak 10 buah pula.Dengan sistem multiple access yang bagus, tidak akan terjadi antrean panjang dan macet. Secara umum, bisa saja sistem multiple access diterapkan dalam berbagai bidang kehidupan, seperti sistem pembayaran di loket PLN, teller bank, dan sebagainya. Tapi pada kenyataannya, penerapan pada bidang telekomunikasilah yang banyak memunculkan multiple access baru.Tren sistem telepon seluler mendongkrak pemakaian multiple access untuk sistem komunikasi bergerak (mobile communication system). Kemajuan yang dicapai oleh telepon seluler bahkan melebihi sistem komunikasi bergerak lain seperti telepon cordless (sekarang juga lagi musim), paging (yang dulu ngetop tahun 1970-1980-an), dan PCS (personal communication standard). Perkembangan telepon seluler yang kian menjadi-jadi dengan berbagai fasilitas ciamik yang andal (semacam MMS, mobile Internet, dan lain- lain), menyebabkan semakin getolnya pencarian-pencarian sistem multiple access baru yang lebih tanggap dan cepat dalam melayani banyak pelanggan.Hingga saat ini dua teknik pendahulu yang masih digunakan adalah FDMA (frequency division multiple access) dan TDMA (time division multiple access).
Pengguna teknik FDMA cukup banyak juga. Salah satunya adalah telepon seluler berbasis AMPS, yang di Indonesia dipakai pada awal munculnya telepon seluler. AMPS (advanced mobile phone system) adalah sistem seluler Amerika Serikat pertama (dan analog) yang dikembangkan oleh AT&T Bell Laboratories pada akhir tahun 1970-an.Pemakai teknik TDMA pun juga cukup banyak. Salah satunya adalah telepon seluler berbasis GSM, yang sekarang lagi marak di Indonesia.
GSM yang mulanya adalah singkatan dari groupe spe’cial mobile diganti menjadi global system for mobile communication untuk keperluan pemasaran yang lebih luas. Ia merupakan standar seluler digital generasi kedua yang dikembangkan oleh Eropa untuk menyatukan sistem selulernya. Bermula dengan dikenalkan pada pasar Eropa tahun 1991, kini GSM telah menjadi standar terpopuler di dunia untuk radio seluler baru dan peralatan komunikasi pribadi. Karena kepopuleran itulah, teknik TDMA ikut terdongkrak dan seolah “kagak ade matinye”.Akan tetapi waktu terus berjalan, dan pesaing-pesaing baru selalu akan muncul untuk mengganti pemain lama. Salah satunya adalah teknik CDMA (code division multiple access).
Dengan lebih banyak kelebihan (dan sedikit kekurangan), teknik yang diusung oleh US Narrowband SpreadSpectrum (IS-95) ini, mulai berkembang dan terus berkembang. GSM yang tidak tinggal diam, tentu akan berusaha mempertahankan takhtanya.
Kita saksikan saja persaingan yang kian marak ini dan barangkali untuk beberapa dekade, kita sementara menjadi penonton saja.FDMAFDMA adalah sistem multiple access yang menempatkan seorang pelanggan pada sebuah kanal berbentuk pita frekuensi (frequency band) komunikasi. Jika satu pita frekuensi dianggap sebagai satu jalan, maka FDMA merupakan teknik “satu pelanggan, satu jalan”. Pada saat pelanggan A sedang menggunakan jalan itu, maka pelanggan lain tidak dapat menggunakan sebelum pelanggan A selesai.Jadi, kalau dalam waktu yang bersamaan ada 100 pelanggan yang ingin berkomunikasi dengan rekannya, maka sudah tentu diperlukan 100 pita frekuensi. Pada penerima terjadi proses despreading yang melibatkan korelasi antara sinyal yang diterima dan replika sinyal kode yang dibangkitkan sendiri oleh suatu generator lokal.Kode yang digunakan pada sistem spread spectrum memiliki sifat acak tetapi periodik sehingga disebut sinyal acak semu ( pseudo random). Kode tersebut bersifat sebagai noise tapi deterministik sehingga disebut juga noise semu ( pseudo noise). Pembangkit sinyal kode ini disebut Pseudo Rando Generator (PRG) atau pseudo noise generator (PNG).
PRG inilah yang akan melebarkan dan sekaligus mengacak sinyal data yang akan dikirimkan. Dalam komunikasi spread spectrum semakin lebar bandwidth akan semakin tahan terhadap jamming dan akan semakin terjamin tingkat kerahasiaannya. Disamping itu akan semakin banyak kanal yang bisa dipakai.
Seperti yang di terangkan oleh Shanon, salah seorang ahli statistik telekomunikasi, dalam ilmu komunikasi dinyatakan bahwa kapasitas kanal akan sebanding dengan bandwidth transmisi dan logaritmik dari S/N-nya. Jadi agar sistem komunikasi dapat bekerja dengan kapasitas kanal yang tetap pada level daya noise yang tinggi (S/N yang rendah), dapat dilakukan dengan jalan memperbesar bandwidth transmisi W. Disamping itu Shannon juga mengemukakan bahwa sebuah kanal dapat mentransmisikan informasi dengan probabilitas salah yang kecil apabila terhadap infromasi tersebut dilakukan pengkodean yang tepat dan rate infromasi yang tidak melebihi kapasitas kanal meskipun kanal tersebut memuat derau acak.Sistem komunikasi spread spectrum sebagai salah satu sistem komunikasi digital, memiliki beberapa kelebihan dibandingkan sistem komunikasi analog yaitu:. RangingDalam teknik spread spectrum sendiri ada beberapa macam cara yang digunakan, yaitu Direct Sequence Spread Spectrum (DSSS), Frequency Hopping Spread Spectrum (FSSS), Time Hopping Spread Spectrum (TSSS) dan Chirp atau Hybrid Spread Spectrum. Pada tiap-tiap metode mempunyai keunggulan sendiri-sendiri, namun secara umum DSSS mempunyai unjuk kerja terbaik untuk gangguan noise dan anti jamming, serta paling susah untuk dideteksi.
Namun ada kekurangan pada DSSS ini, yang sering menjadi kendala dalam implementasinya, yaitu pada proses sinkronisasi sinyal yang diterima dengan sinyal dari generator noise lokal pada penerima.Note: Need Pathloss 4.0?? Pathloss 4.0 Full Version?? Pathloss with coverage??
Pathloss 4.0 with interference?? Pathloss 4.0 with background network?? Path loss 4.0??TEms 6 or 8?? Global Mapper 10??
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