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2/23/10 12:44 AMPathloss: Pathloss 4.0
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Home Pathloss 4.0 Pathloss 5.0 Download Telco Tools Refference Movie
1. First Click Module >> Network >> Site Data >> Site List >> Import >> Link text file
2. When you are in the Import Link dialog box, you will see a list of values that can be imported. At the end ofeach line put a space and the number of the column (field) in your CSV file as shown below.
3. Setting field delimiter, coordinate format, latitudes, longitudes, unit, grid unit, hemisphere, polarization, file names, etclike your csv data.
Once you have defined the fields you can click Save definition file for reuse later. Make sure you set the otheroptions in the dialog to match your data source.
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a. Any unwanted signal
b. Copy of wanted signal delayed due to multipath propagation
c. An adjacent channel’s signal traveling over the same link
d. A signal from another radio link or RF source
There are two interference classes:
a. Between the same system ( Intra System Case): Controllable
b. Between different systems ( Inter System Case): Un controllable
Intrasystem
This type of interference is caused by an undesired signal generated within the system.Two possible cases:
A. Overreach interference
Solution:a. Plan for a longer overreach path to add additional free-‐space loss to the
undesired signal.b. Maximize antenna discrimination against the overreach path.c. Use a suitable route such that the overreach path can be blocked by the terrain
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a. Use antenna with a very high front-‐to-‐back ratio.
b. Worst case: Switch to 4 Frequency plan
Intersystem Interference
a. Caused by reception of an unwanted transmission from of a different system.
b. Can be coordinated by adjusting the antenna discrimination and receiver selectivity, andchoosing proper frequency plans.
c. Best Option: Coordination, control, and sometimes compromising on the radio channelthrough direct negotiation with the other operator on the same Frequency bands.
d. Note: With proper Government run Spectrum management coordination shall nothappen.
2. Calculating Interference Using Pathloss 4.0Intra system interference can be calculated by following method. Go to Network Page byclicking ctrl N – Defaults menu – Link Label. Select TX Frequency & Polarization – PressRest All as per shown in Fig. Have a look to your network & make sure that all linksFrequencies & Polarizations are correct according to your plan. If there is any mistake inany link please go to its work sheet & make it correct.
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Select Interference – Calculate Intra and the Interference Calculation dialog box will bedisplayed. Enter the parameters for the calculation and press Calculate. The calculationwill be carried out and saved in the same directory as the network diagram. If a secondinterference calculation is carried out it will overwrite the first when it is saved.
Error Log
Once the calculation is completed a number of reports can be viewed. The Error Logshould be viewed to make sure that there are no missing files and that the calculation isvalid. Select Interference – View Error Log
a. Every Site must have Call Signb. Antenna files and Radio files used in Link Budgeting must be in the selected
directoriesc. Frequency Assign to every linkd. Every Link have PL4 file
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Image 9The Case Detail option provides all the technical information on each interference case.
The Hi-‐Lo Violations should be viewed first to make sure that all sites are either transmittinghigh or transmitting low. The only exception to this rule is if different frequency bands are usedat a site
When you are satisfied with the results of the interference calculation the PL 4 files associated
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When you are satisfied with the results of the interference calculation the PL 4 files associatedwith the interference study can be updated. Select Interference – Update Pathloss Files. Thechoice is either to update the threshold degradation or to remove the threshold degradation.
Posted by Pathloss 4.0 Labels: Pathloss 4.0
PATHLOSS 4.0
MICROWAVE REPEATERS
1. PASSIVE REPEATER
Microwave repeaters can be classified as:
a Passive Repeaters
b. RF Repeaters
WHY USE THEM ?
Ø When a microwave hop is required in a place which has some unavoidable physicalobstacles.
Ø Where a mountain peak has to be surmounted which may be so inaccessible that powercannot be provided for a usual active repeater.
There are two main types of Passive Repeaters:
1 Passive or plane reflectors
2 Back-‐to-‐back antenna passives
Passive repeaters have the following advantages over active sites:
Ø No power is required;
Ø No regular road access is required;
Ø No equipment housing is needed;
Ø They are environmentally friendly;
Ø Little or no maintenance is required.
PATHLOSS 4.0 (MICROWAVE REPEATERS)at 4:45 PM | 0 comments Links to this post
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Ø Use of back-‐to-‐back antennas are practical when the reflection angle is
Ø large. The gain of a repeater with back-‐to-‐back antennas is given by:
2. CREATEING PASSIVE REPEATER USING PATHLOSS 4.0The Aloum to Lolodorf CRTV link has been used as an example in this documentStep 1:The first step is to generate and save two path profiles and link budgets:Profile 1 -‐ Site 1(Aloum) to Passive (Lolodorf Passive)Profile 2 -‐ Passive (Lolodorf Passive) to Site 2 (Lolodorf CRTV)The passive repeater site has to have the same co-‐ordinates and elevation in bothprofiles.When entering the frequency for the second path profile use the same frequency andHi/Lo configuration as the first profile but change the polarisation.It is not necessary to enter the microwave terminal equipment for the passive repeatersite as they are not used in the final link budget. It is advisable to enter the antennainformation for the passive repeater site as this will provide a link budget starting pointwhen optimising the link performance.Step 2:Open Profile 1 (Aloum-‐Lolodorf Passive) in the Worksheet section of PL4.
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Step 3:1. Click on the Operations tab and select Create Passive Repeater.
2. Next select the type of passive repeater to be created Back-‐to-‐Back Antennas
3. Select Profile 2 (Lolodorf Passive-‐Lolodorf CRTV.pl4) from the list of profiles
4. The second profile will be joined to the first and the passive repeater site indicated.Save the new profile under a name indicting that it is a passive repeater profile (Aloum-‐
Lolodorf Passive-‐Lolodorf CRTV.pl4).
Step 4:The connection between the two passive antennas has to be made. Click on the P symbolto open the Passive Repeater information and enter the cable information
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Step 5:Adjust the antenna sizes, TX power outputs etc. to ensure that the link budget meets theperformance requirements for the link.Once satisfied with the results save the profile.Reports:Two reports need to be generated for the passive repeater link:1. The Full Report – this provides the configuration and performance information of thecomplete link, but excludes the passive repeater site.2. The passive repeater report – this provides configuration information on the passiverepeater site.Full report:Select Reports – Full Report from the menu at the top of the page