PathLoss Guidelines 13Mar06

PATHLOSS GUIDELINES Page 1 of 19

I. GUIDELINES IN PREPARATION OF PATH PROFILE A.

REQUIREMENTS 1. PathLoss Tool User must be familiar with the basic microwave transmission concept. 2. PathLoss Tool User must be provided with site information such as Site Name & Site Coordinates, together with link propagation criteria (i.e. K-factor & Fresnel Zone Criteria) that is i s being followed by the end-user/customer.

B.

PROCEDURE 1. From the Summary Module, input the Site Name and Site Coordinates of both stations.


** In case of Multiple links, Site Name and Coordinates can be entered on the Site List from the Grid Module.

2. Generate the path profile from the Terrain Data Module by clicking generate profile button. Be sure to set the primary terrain data and its directory first before generating the profile.


**Be sure to set the primary terrain data and its directory first before generating the profile.


3. In cases where additional vegetation or building is needed, input the corresponding data on the terrain data sheet.


4. Assign antenna heights for both stations on the Antenna Height Module. Be sure to consider tower height and loading for existing station when assigning the antenna height.


5. Counter-check the visual display of the profile on the Print Profile Module.

6. In case of obstruction, adjust the tower height on one station accordingly until the desired clearance is achieved.



II. GUIDELINES IN PREPARATION OF LINK BUDGET A.

REQUIREMENTS 1. PathLoss Tool User must be provided with the following information: -

2.

Region (North, Center or South) Site Names / Site Codes Coordinates (Latitude, Longitude) Radio Capacity (2E1, 4E1, 8E1,16E1 or STM1) Radio Configuration (Unprotected or Protected) Building Height (if roof-mounted) Tower Height Antenna Height Antenna Type (Andrew, RFS or other) Frequency Band to be Used Approved Frequency Channel to be used For Protected Configuration using 2-Antenna System, type of RF Cable (Low Loss Cable) or Waveguide to be used.

PathLoss Tool User must be provided with the required availability criteria for each link as well as desired fade margin and other design factors if necessary. ** Example for Pakistan Project: Link Availability (at least 99.999%) and Fade Margin (30dB for SDH and 35dB for PDH).

B.

PROCEDURE 1. From the Summary Module, input the Site Name and Site Coordinates of both stations. 2. Input the frequency band to be used on the frequency potion on the Summary Module.


3. Generate the path profile from the Terrain Data Module by clicking generate profile button. Be sure to set the primary terrain data and its directory first before generating the profile (see Procedure No.2, Path Profile Guidelines).

4. Assign antenna heights for both stations on the Antenna Height Module. Be sure to consider tower height and loading for existing station when assigning the antenna height (see Procedure No.3, Path Profile Guidelines).

5.

From the Worksheet Module, perform the following items. a). Assign the corresponding Rain Region based from ITU Standard. ** ITU has designated Rain Region N for Luzon and some portion Visayas while Rain Region P for Mindanao and rest of Visayas.


b). Select the Antenna Polarization to be used.

c). Select the Antenna Type to be used. Click both to apply to both station the selected antenna type. **Antenna type to be selected must be applicable on the same frequency band that will be used.


d). From the equipment list, choose the equipment type to be used with consideration of the required Radio capacity(4,8 or16E1) and Configuration (1+0 or 1+1).

**In case of 1+1 HS Configuration. Hybrid Loss must be considered for direct mount configuration and RF Cable/Waveguide Loss must be distinct for indirect mount configuration. Hybrid Loss=3dB/station Waveguide Loss is depending on the type of cable to be used.



e). Input the channel frequency to be used. (Approved frequency channel must be secured first from end user/customer before assigning). **High or Low Side must also be selected during selecting desired frequency. **For Multi-links, PathLoss Tool User shall decide the point frequency and polarization appropriate for the link based on existing frequencies within respectable distance from subject link. Interference report should be checked to confirm possible interference.


f. Check the Link Availability **For short distance hops, additional attenuation can be assigned in order to protect the ODU from receiving very high receive levels.

**PathLoss Tool User shall decide the antenna diameter size required for the link based on the Link Availability (at least 99.999%) and Fade Margin (30dB for SDH and 35dB for PDH).


C.

Commonly Used Standards on Pathloss Designing/Updating (Reference: Pakistan Project)

1. Proper legends should be followed for the site/link layers and link attributes. Example: Table 1 - PathLoss Layers

Site Layers On-Air Planned Micro/Dart DTE BSC MSC

: NEC and other vendor sites which are On-Air : NEC and other vendor sites which are planned (Other vendor planned sites should be informed by Customer) : Small-capacity (other vendor) sites which are On-Air : PTCL Site : BSC Site : MSC Site

Link Layers NEC Installed NEC Planned Other Installed Other Planned

: : : :

NEC links which are currently operational NEC links which are still under planning Other vendor links which are currently operational Other vendor links which are still under planning


2.

Below are the legends commonly used in PathLoss Tool.

Table 2 – Legends for PathLoss Layers


3.

Link Planning Form Table 3 - Link Planning Form


** PathLoss Tool User shall attach the Link Budget to the Link Planning Form, wherein copies shall be provided to, a. b. c. d.

Project Manager Person-in-Charge, Customer Side (Txn Dept.) NESIC SV & Installation Team NEC, if necessary

During Pre-Test/Installation:

1. NESIC Installation Team shall confirm the data in the Link Planning Form and the attached Link Budget.

2. If any parameter has to be changed, the person/party modifying the data should accomplish a new Link Planning Form using the same Reference No. indicating the Revision No. and place comments/notes regarding the changes. The newly accomplished Link Planning Form has to be attached to the previous Link Planning Form and provide a copy to the PathLoss Tool User in order to prepare the revised Link Budget. New Link Planning Form with revised Link Budget will be provided to:

a. b. c. d.

Project Manager Person-in-Charge, Customer Side (Tx Dept.) NESIC SV on site NEC, if necessary

During PAT: 1. NESIC Installation Team should have a copy of both the Link Planning Form and Link Budget. All data in the Link Planning Form should be reconfirmed at the site by both Customer/Client and NESIC Testing Team. Other missing data in the Link Planning Form should be completed (no blanks should be left-out) .

2. Both parties shall fix their signature on the attached Link Budget.

3. After PAT, NESIC Installation Team shall give a copy of the completed Link Planning Form with the attached signed Link Budget to Project Manager or Planning Group for filing and record purposes.


Updating of PathLoss Tool 1. PathLoss Tool User shall immediately update the PathLoss Data after receiving Link Planning Form. PathLoss Data shall be updated with the information provided in the Link Planning Form with attached signed Link Budget. Layers and Link attributes should be observed in reference to Table2.

2. PathLoss Tool User shall provide duplicate copies of the final Link Planning Form to: a. Project Manager b. Person-in-Charge, Customer Side (Tx Dept.) c. NESIC SV on site d. NEC, if necessary e. Warehouse, if logistics is part of SOW.

3. Customer TXN Planning Department may update their planning tool using the same procedure and forms.

Modifications Required in the Future **When a link is to be modified for any parameters in the future, the Link Planning Form should be used. The Reference No. shall remain the same, the Revision No. should be indicated with comments/notes regarding the modification. Examples of link modifications are, a. b. c. d.

Change of antenna heights Change of frequency channel assignment Change of radio capacity Link is dismantled/removed

PathLoss Tool Updated **After updating the PathLoss Data, a Check Mark (√) has to be placed on the tick box beside “Final” and place the date when the final confirmed parameters where entered into the PathLoss Data. This shall be the confirmation that PathLoss Tool was updated.

PathLoss Guidelines 13Mar06

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