pathcalc_usermanual

Path Calculator User Guide

© 2007 AS SAF Tehnika

Revision History

Revision Date Comments

1.0 January 29, 2007 Initial release.

Table of Contents

1 Overview..............................................................................................................4 1.1 Configuration Options ......................................................................................4 1.2 Work Sheet Appearance...................................................................................4

2 Work Sheets .........................................................................................................6 2.1 CFM 1+0 .......................................................................................................6 2.2 CFM 1+1 HSB.................................................................................................8 2.3 CFM 1+1 SD................................................................................................. 11 2.4 CFM 1+1 FD................................................................................................. 14 2.5 CFQ 1+0...................................................................................................... 16 2.6 CFQ 1+1 HSB............................................................................................... 19 2.7 CFQ 1+1 SD................................................................................................. 22 2.8 CFQ 1+1 FD ................................................................................................. 25 2.9 Rain Zone .................................................................................................... 27

3 References ......................................................................................................... 28 4 SAF Tehnika Contacts........................................................................................... 28

Path Calculator User Guide. Rev. 1.0 © 2007 AS SAF Tehnika

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1 Overview The present User Guide describes the SAF Tehnika proprietary Path Calculator – a point-to-point radio link calculation tool designed to detect various parameters essential for planning and installing the digital microwave data transmission systems, e.g. link availability, fade margin, received signal level, etc. The Path Calculator assists system designers in selecting the equipment with appropriate specifications, considering the climatic conditions, necessary link capacity and available location for site setup. It provides the opportunity to choose between wide range of operating frequencies, equipment configuration options and operating parameters in order to establish reliable and efficient data transmission.

The SAF Tehnika Path Calculator is based on the ITU-R recommendation P.530-11.

The Path Calculator is designed as a Microsoft Excel file, including nine work sheets – eight of them are supposed for calculating the link related parameters, each of these eight sheets represents a different link configuration option. The ninth sheet provides a Rain Zone map which can be used to determine the precipitation for a particular area.

To perform calculation some parameter values should be known in advance:

Distance between antennas and/or geographic coordinates of the sites

Antennas height over sea level

Rain zone

Radio transmitter output power

Frequency

After the calculation result is received it is possible to judge whether selected parameters ensure the necessary system performance in terms of link availability, fade margin, received signal level, etc, considering the particular needs. If customer requires higher Availability or Fade margin, it is possible to readjust antennas, radio output power, or operating frequency till desired level is achieved.

1.1 Configuration Options CFM links:

1+0 (unprotected link)

Protected configuration:

1+1 HSB (Hot Stand By)

1+1 SD (Space Diversity)

1+1 FD (Frequency Diversity)

CFQ links:

1+0 (unprotected link)

Protected configuration:

1+1 HSB (Hot Stand By)

1+1 SD (Space Diversity)

1+1 FD (Frequency Diversity)

1.2 Work Sheet Appearance The work sheet appearance varies with the selected configuration option. Still calculation work sheets have several common properties:

− Title “Path Calculation” displaying the chosen configuration option.

− The cells with grey background are intended for data input.

− The cells with yellow background and containing text in red allow the choice between parameter options.

− The cells with scroll arrow (appearing on the right after selecting the cell) allow the choice between options listed in the drop-down box.

− The cells with yellow background contain the result of calculating availability.

Each of calculation work sheets contains cells with general information, which are optional for filling in:

Date: the current date is displayed automatically, or user can enter desired date manually.

Project: the name of the project can be entered for reference purposes.

Site A: the name of the site A can be entered.

Site B: the name of the site B can be entered.

The example of calculation work sheet is presented in Fig. 1.

Fig. 1. Path Calculation work sheet for CFM 1+0 configuration.


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2 Work Sheets

2.1 CFM 1+0 The CFM 1+0 configuration is an unprotected radiolink configuration for sites equipped with CFM series units.

The “Path Calculation 1+0” work sheet (see Fig. 1) includes the following rows:

Use this listbox to specify the distance between sites Choose the option for data input from the drop-down list – either “distance between sites” or “exact longitude/latitude of each site”. The first one requires the manual input of distance and approximate coordinates. Choosing the second option only exact coordinates input (degrees, minutes, seconds and hemisphere label – N/S and E/W) is necessary, the distance will be calculated automatically.

Radio capacity Enter the desired radio link capacity. It is possible to choose between 4, 8, 16 or 34 Mbps – the capacity can be entered manually or using the drop-down list appearing after pressing the scroll arrow.

Annual temperature

Enter the average annual temperature in Celsius degrees.

Rain zone

Choose the letter according to the approximate amount of precipitation in the area. Rain Zones comply with Recommendation ITU-R P.837-4 and can be found in 'Rain Zone' sheet. The possible variants with their corresponding values are listed in Table 1 (these values can also be seen in a pop-up note in the “Path Calculator” work sheet).

Table 1 Rain Zone Amount of precipitation, mm/h

A 8

B 12

C 15

D 19

E 22

F 28

G 30

H 32

J 35

K 42

L 60

M 63

N 95

Q 115

P 145

Latitude A

Enter the latitude for site A.

Longitude A

Enter the longitude for site A.


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Latitude B

Enter the latitude for site B.

Longitude B

Enter the longitude for site B.

Manual Distance Input

This row appears only if “distance between sites” option has been chosen in the cell “Use this listbox to specify the distance between sites”. Enter the distance between sites.

Calculated distance This cell contains the calculation result for distance between sites based on the exact coordinates entered, in case of using “exact longitude/latitude of each site” option. If “distance between sites” option has been chosen, the value of this cell will be equal to the distance entered in “Manual Distance Input” cell.

Transmitter Power Enter the transmitter power in dBm or choose the desired value from the drop-down list. The maximum transmitter power depends on operating frequency. The maximum transmitter power values corresponding to particular frequencies are presented in Table 2 (these values can also be seen in a pop-up note in the “Path Calculator” work sheet).

Table 2 Frequency, GHz Maximum transmitter power, dBm

4.5 33

7 27

8 27

10.5 27

11 27

13 20

15 20

18 19

23 19

26 19

32 16

38 14

Frequency Enter the desired frequency in GHz or choose the necessary value from the drop-down list. The possible choices are the following: 4.5; 7; 8; 10.5; 11; 13; 15; 18; 23; 26; 32; 38.

Antenna A height over sea level

Enter the antenna height over sea level (in meters) for the site A.

Antenna B height over sea level

Enter the antenna height over sea level (in meters) for the site B.

Choose type of antenna

Choose an option from the drop-down list. The options “Comhat-Provexa” and “DG antennas”, if chosen, provide the automatic antenna gain input (in dBi) in the appropriate cells. In case “Other” option has been chosen, it is necessary to enter the antenna gain value manually (the cells entitled “Manual antenna gain input” will appear after choosing this option).


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Antenna A

Enter the site A antenna diameter (in meters) or choose necessary value from the drop-down list. The possible options for “Comhat-Provexa” antennas are following: 0.3; 0.6; 1.2; 1.8; 2.4; 3; L250. The options for “DG antennas” and other antennas are: 0.3; 0.6; 0.8; 1.2; 1.8; 2; 2.4; 3.

Antenna B Enter the site B antenna diameter (in meters) or choose necessary value from the drop-down list. The possible options for “Comhat-Provexa” antennas are following: 0.3; 0.6; 1.2; 1.8; 2.4; 3; L250. The options for “DG antennas” and other antennas are: 0.3; 0.6; 0.8; 1.2; 1.8; 2; 2.4; 3.

Losses In case of using antennas with waveguide it is necessary to enter the level of losses in dB.

Received signal level This cell will contain the calculated received signal level in dBm.

Fade Margin These two cells will contain the calculated fade margin values corresponding to the particular BER level (10-3 and 10-6).

Automatic Rx Threshold input

This cell allows switching between automatic and manual Rx Threshold input, using scroll arrow to open the drop-down list containing the mentioned options. In case of choosing automatic input the Rx threshold value will be entered automatically. If manual input was preferred, it will be necessary to enter the desired threshold value in additional cells appearing after this option has been chosen.

Multipath Availability The cells under this heading will represent the calculated multipath availability (%) at particular BER levels (10-3 and 10-6 respectively) for both vertical and horizontal antenna polarization.

Rain Availability

The cells under this heading will represent the calculated link availability (%) in rain conditions at particular BER levels (10-3 and 10-6 respectively) for both vertical and horizontal antenna polarization.

Multipath+Rain Availability

The cells under this heading will represent the calculated aggregate multipath and rain availability (%) at particular BER levels (10-3 and 10-6 respectively) for both vertical and horizontal antenna polarization.

2.2 CFM 1+1 HSB The CFM 1+1 HSB configuration is a protected link configuration. In HSB mode, both the incoming (Rx) and outgoing (Tx) traffic is switched to either one link or other, only one link is operating; the transmitter of the inactive outdoor unit (ODU) is switched off at each side.

Fig. 2

The “Path Calculation 1+1 HSB” work sheet (Fig. 2) includes the following rows:



Annual temperature


Rain zone


Latitude A


Longitude A


Latitude B



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10

Longitude B






Frequency

Enter the desired frequency in GHz or choose the necessary value from the drop-down list. The possible choices are the following: 4.5; 7; 8; 10.5; 11; 13; 15; 18; 23; 26; 32; 38.





Choose 1+1 HSB configuration mode

Either “Using 2 antennas and coupler” or “Using 4 antennas” option can be chosen from the drop-down list. In case of choosing the first one, the cells intended for coupler parameters input will appear. When second option is chosen, it will be possible to view/enter the parameters of four antennas.

Using 2 antennas and coupler

It will be necessary to enter (or select from the drop-down list) the diameters of A and B antennas, choosing from the 0.3; 0.6; 1.2; 1.8; 2.4; 3; L250 range if “Comhat-Provexa” antennas are used, or 0.3; 0.6; 0.8; 1.2; 1.8; 2; 2.4; 3 if “DG antennas” or “Other” option was selected from the “Choose type of antenna” drop-down list. The “Comhat-Provexa” and “DG antennas” options provide automatic input of antenna gain in the appropriate cells. If “Other” option has been chosen the antenna gain should be entered manually in cells under the heading “Manual antenna gain input”.

The coupler parameters are coupler attenuation values which should be entered for both site A and site B primary and standby links.

Using 4 antennas It is necessary to enter (or select from the drop-down list) the diameters (and antenna gain, in case of using “Other” antennas) of site A and site B antennas – the options are the same as when using 2 antennas and coupler. The equal values (antenna diameter and gain) of antenna A2 and antenna B2 will be entered in the appropriate cells automatically.


Received signal level

This cell will contain the calculated received signal level in dBm. The value for the standby link will be displayed if “Using 2 antennas and coupler” option has been chosen.


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Fade Margin

These two cells will contain the calculated fade margin values corresponding to the particular BER level (10-3 and 10-6). The values for the standby link will be displayed if “Using 2 antennas and coupler” option has been chosen.



Multipath Availability The cells under this heading will represent the calculated multipath availability (%) at particular BER levels (10-3 and 10-6 respectively) for both vertical and horizontal antenna polarization. The values for the standby link will be displayed if “Using 2 antennas and coupler” option has been chosen.

Rain Availability

The cells under this heading will represent the calculated link availability (%) in rain conditions at particular BER levels (10-3 and 10-6 respectively) for both vertical and horizontal antenna polarization. The values for the standby link will be displayed if “Using 2 antennas and coupler” option has been chosen.


The cells under this heading will represent the calculated aggregate multipath and rain availability (%) at particular BER levels (10-3 and 10-6 respectively) for both vertical and horizontal antenna polarization. The values for the standby link will be displayed if “Using 2 antennas and coupler” option has been chosen.

2.3 CFM 1+1 SD The CFM 1+1 SD configuration is a protected link configuration with four antennas necessary. In this configuration one transmitter and two receivers operate for each direction, and only one frequency pair is used.

Fig. 3

The “Path Calculation 1+1 SD” work sheet (Fig. 3) includes the following rows:

Use this listbox to specify the distance between sites

Choose the option for data input from the drop-down list – either “distance between sites” or “exact longitude/latitude of each site”. The first one requires the manual input of distance and approximate coordinates. Choosing the second option only exact coordinates input (degrees, minutes, seconds and hemisphere label – N/S and E/W) is necessary, the distance will be calculated automatically.


Annual temperature Enter the average annual temperature in Celsius degrees.

Rain zone Choose the letter according to the approximate amount of precipitation in the area. Rain Zones comply with Recommendation ITU-R P.837-4 and can be found in 'Rain Zone' sheet. The possible variants with their corresponding values are listed in Table 1 (these values can also be seen in a pop-up note in the “Path Calculator” work sheet).

Latitude A Enter the latitude for site A.

Longitude A Enter the longitude for site A.

Latitude B Enter the latitude for site B.


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13

Longitude B






Frequency








Enter (or select from the drop-down list) the diameters (and antenna gain, in case of using “Other” antennas) of two site A and two site B antennas. The options are the following: 0.3; 0.6; 1.2; 1.8; 2.4; 3; L250 range if “Comhat-Provexa” antennas are used, or 0.3; 0.6; 0.8; 1.2; 1.8; 2; 2.4; 3 if “DG antennas” or “Other” option was selected from the “Choose type of antenna” drop-down list.

Antenna vertical separation

Enter the distance (in meters) between the antennas at each site.

Losses

In case of using antennas with waveguide it is necessary to enter the level of losses in dB.





Multipath Availability

The cells under this heading will represent the calculated multipath availability (%) at particular BER levels (10-3 and 10-6 respectively) for both vertical and horizontal antenna polarization.

Rain Availability




2.4 CFM 1+1 FD The CFM 1+1 FD configuration is a protected link configuration with two frequency pairs used. In FD mode, the outgoing (Tx) traffic at each site is passed to both ODUs, the transmitters of both ODUs are always switched on; the incoming signal (Rx) is picked from one of the indoor units (IDU), depending on the received signal level and alarm status of the link. The FD configuration allows using two or four antennas.

Frequency diversity calculation applies only to the following ranges of parameters:

2 ≤ f ≤ 11 GHz

30 ≤ d ≤ 70 km

∆f / f ≤ 5%

Fig. 4

The “Path Calculation 1+1 FD” work sheet (Fig. 4) includes the following rows:


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Radio capacity

Enter the desired radio link capacity. It is possible to choose between 4, 8, 16 or 34 Mbps – the capacity can be entered manually or using the drop-down list appearing after pressing the scroll arrow.



Latitude A




Longitude B Enter the longitude for site B.

Manual Distance Input This row appears only if “distance between sites” option has been chosen in the cell “Use this listbox to specify the distance between sites”. Enter the distance between sites.


Transmitter Power

Enter the transmitter power in dBm or choose the desired value from the drop-down list. The maximum transmitter power depends on operating frequency. The maximum transmitter power values corresponding to particular frequencies are presented in Table 2 (these values can also be seen in a pop-up note in the “Path Calculator” work sheet).

Frequency


Choose 1+1 FD configuration mode The possible options are “using 2 antennas” and “using 4 antennas”. In the latter case it is necessary to specify the “Transmitter power FD” and “Frequency FD” parameters values. The ranges for these parameters are the same as for “Transmitter Power” and “Frequency”.




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Enter (or select from the drop-down list) the antennas diameters (and antenna gain, in case of using “Other” antennas). The options are the following: 0.3; 0.6; 1.2; 1.8; 2.4; 3; L250 range if “Comhat-Provexa” antennas are used, or 0.3; 0.6; 0.8; 1.2; 1.8; 2; 2.4; 3 if “DG antennas” or “Other” option was selected from the “Choose type of antenna” drop-down list. In case of using two antennas there will be two rows intended for antenna data input, in case of using four antennas the additional rows for “Antenna A FD” and “Antenna B FD” will appear.

Main frequency

Enter the main frequency in GHz.

Diversity frequency

Enter the diversity frequency in GHz.






Multipath Availability The cells under this heading will represent the calculated multipath availability (%) at particular BER levels (10-3 and 10-6 respectively) for both vertical and horizontal antenna polarization.

Rain Availability




2.5 CFQ 1+0 For CFQ equipment the factor determining radio capacity is modulation type. The CFQ 1+0 configuration is an unprotected radiolink configuration for sites equipped with CFQ units.

Fig. 5

The “Path Calculation 1+0” work sheet (Fig. 5) includes the following rows:


Radio modulation

Enter the necessary type of modulation. It is possible to choose between QPSK, QAM16, QAM32, QAM64, or QAM128 – the modulation can be entered manually or using the drop-down list appearing after pressing the scroll arrow. Depending on the selected modulation type the capacity will differ. The corresponding values are presented in Table 3.

Table 3 Modulation type Max capacity, Mbps

QPSK 34

QAM16 75

QAM32 95

QAM64 115

QAM128 155


Rain zone Choose the letter according to the approximate amount of precipitation in the area. Rain Zones comply with Recommendation ITU-R P.837-4 and can be found in 'Rain Zone' sheet.


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The possible variants with their corresponding values are listed in Table 1 (these values can also be seen in a pop-up note in the “Path Calculator” work sheet).

Latitude A


Longitude A


Latitude B


Longitude B


Manual Distance Input This row appears only if “distance between sites” option has been chosen in the cell “Use this listbox to specify the distance between sites”. Enter the distance between sites.

Calculated distance

This cell contains the calculation result for distance between sites based on the exact coordinates entered, in case of using “exact longitude/latitude of each site” option. If “distance between sites” option has been chosen, the value of this cell will be equal to the distance entered in “Manual Distance Input” cell.

Transmitter Power

Enter the transmitter power in dBm or choose the desired value from the drop-down list. The maximum transmitter power depends on operating frequency. The maximum transmitter power values corresponding to particular frequencies are presented in Table 4 (these values can also be seen in a pop-up note in the “Path Calculator” work sheet).

Table 4 Frequency, GHz Maximum transmitter power, dBm

7 24

13 22

18 19

38 14

Frequency Enter the desired frequency in GHz or choose the necessary value from the drop-down list. The possible choices are the following: 7; 13; 18; 38.



Antenna B height over sea level Enter the antenna height over sea level (in meters) for the site B.

Choose type of antenna Choose an option from the drop-down list. The options “Comhat-Provexa” and “DG antennas”, if chosen, provide the automatic antenna gain input (in dBi) in the appropriate cells. In case “Other” option has been chosen, it is necessary to enter the antenna gain value manually (the cells entitled “Manual antenna gain input” will appear after choosing this option).

Antenna A

Enter the site A antenna diameter (in meters) or choose necessary value from the drop-down list. The possible options for “Comhat-Provexa” antennas are following: 0.3; 0.6; 1.2; 1.8; 2.4; 3; L250. The options for “DG antennas” and other antennas are: 0.3; 0.6; 0.8; 1.2; 1.8; 2; 2.4; 3.


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Antenna B

Enter the site B antenna diameter (in meters) or choose necessary value from the drop-down list. The possible options for “Comhat-Provexa” antennas are following: 0.3; 0.6; 1.2; 1.8; 2.4; 3; L250. The options for “DG antennas” and other antennas are: 0.3; 0.6; 0.8; 1.2; 1.8; 2; 2.4; 3.



Fade Margin

These two cells will contain the calculated fade margin values corresponding to the particular BER level (10-3 and 10-6).

Automatic Rx Threshold input This cell allows switching between automatic and manual Rx Threshold input, using scroll arrow to open the drop-down list containing the mentioned options. In case of choosing automatic input the Rx threshold value will be entered automatically. If manual input was preferred, it will be necessary to enter the desired threshold value in additional cells appearing after this option has been chosen.



Rain Availability




2.6 CFQ 1+1 HSB The CFQ 1+1 HSB configuration is a protected link configuration. In HSB mode, both the incoming (Rx) and outgoing (Tx) traffic is switched to either one link or other, only one link is operating; the transmitter of the inactive outdoor unit (ODU) is switched off at each side.

Fig. 6

The “Path Calculation 1+1 HSB” work sheet (Fig. 6) includes the following rows:


Radio modulation


Annual temperature


Rain zone



Longitude A


Latitude B



20


21

Longitude B






Frequency

Enter the desired frequency in GHz or choose the necessary value from the drop-down list. The possible choices are the following: 7; 13; 18; 38.





Choose 1+1 HSB configuration mode

Either “Using 2 antennas and coupler” or “Using 4 antennas” option can be chosen from the drop-down list. In case of choosing the first one, the cells intended for coupler parameters input will appear. When second option is chosen, it will be possible to view/enter the parameters of four antennas.

Using 2 antennas and coupler

It will be necessary to enter (or select from the drop-down list) the diameters of A and B antennas, choosing from the 0.3; 0.6; 1.2; 1.8; 2.4; 3; L250 range if “Comhat-Provexa” antennas are used, or 0.3; 0.6; 0.8; 1.2; 1.8; 2; 2.4; 3 if “DG antennas” or “Other” option was selected from the “Choose type of antenna” drop-down list. The “Comhat-Provexa” and “DG antennas” options provide automatic input of antenna gain in the appropriate cells. If “Other” option has been chosen the antenna gain should be entered manually in cells under the heading “Manual antenna gain input”.

The coupler parameters are coupler attenuation values which should be entered for both site A and site B primary and standby links.

Using 4 antennas It is necessary to enter (or select from the drop-down list) the diameters (and antenna gain, in case of using “Other” antennas) of site A and site B antennas – the options are the same as when using 2 antennas and coupler. The equal values (antenna diameter and gain) of antenna A2 and antenna B2 will be entered in the appropriate cells automatically.



This cell will contain the calculated received signal level in dBm. The value for the standby link will be displayed if “Using 2 antennas and coupler” option has been chosen.


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Fade Margin

These two cells will contain the calculated fade margin values corresponding to the particular BER level (10-3 and 10-6). The values for the standby link will be displayed if “Using 2 antennas and coupler” option has been chosen.



Multipath Availability The cells under this heading will represent the calculated multipath availability (%) at particular BER levels (10-3 and 10-6 respectively) for both vertical and horizontal antenna polarization. The values for the standby link will be displayed if “Using 2 antennas and coupler” option has been chosen.

Rain Availability

The cells under this heading will represent the calculated link availability (%) in rain conditions at particular BER levels (10-3 and 10-6 respectively) for both vertical and horizontal antenna polarization. The values for the standby link will be displayed if “Using 2 antennas and coupler” option has been chosen.


The cells under this heading will represent the calculated aggregate multipath and rain availability (%) at particular BER levels (10-3 and 10-6 respectively) for both vertical and horizontal antenna polarization. The values for the standby link will be displayed if “Using 2 antennas and coupler” option has been chosen.

2.7 CFQ 1+1 SD The CFQ 1+1 SD configuration is a protected link configuration with four antennas necessary. In this configuration one transmitter and two receivers operate for each direction, and only one frequency pair is used.

Fig. 7

The “Path Calculation 1+1 SD” work sheet (Fig. 7) includes the following rows:



Radio modulation Enter the necessary type of modulation. It is possible to choose between QPSK, QAM16, QAM32, QAM64, or QAM128 – the modulation can be entered manually or using the drop-down list appearing after pressing the scroll arrow. Depending on the selected modulation type the capacity will differ. The corresponding values are presented in Table 3.

Annual temperature


Rain zone


Latitude A


Longitude A


Latitude B



23


24

Longitude B






Frequency








Enter (or select from the drop-down list) the diameters (and antenna gain, in case of using “Other” antennas) of two site A and two site B antennas. The options are the following: 0.3; 0.6; 1.2; 1.8; 2.4; 3; L250 range if “Comhat-Provexa” antennas are used, or 0.3; 0.6; 0.8; 1.2; 1.8; 2; 2.4; 3 if “DG antennas” or “Other” option was selected from the “Choose type of antenna” drop-down list.

Antenna vertical separation

Enter the distance (in meters) between the antennas at each site.

Losses








Rain Availability




2.8 CFQ 1+1 FD The CFQ 1+1 FD configuration is a protected link configuration with two frequency pairs used. The FD configuration allows using two or four antennas.

Frequency diversity calculation applies only for the following ranges of parameters:

2 ≤ f ≤ 11 GHz

30 ≤ d ≤ 70 km

∆f / f ≤ 5%

Fig. 8

The “Path Calculation 1+1 FD” work sheet (Fig. 8) includes the following rows:




25


26

Radio modulation







Longitude B






Frequency


Choose 1+1 FD configuration mode.

The possible options are “using 2 antennas” and “using 4 antennas”. In the latter case it is necessary to specify the “Transmitter power FD” and “Frequency FD” parameters values. The ranges for these parameters are the same as for “Transmitter Power” and “Frequency”.






Choose an option from the drop-down list. The options “Comhat-Provexa” and “DG antennas”, if chosen, provide the automatic antenna gain input (in dBi) in the appropriate cells. In case “Other” option has been chosen, it is necessary to enter the antenna gain


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value manually (the cells entitled “Manual antenna gain input” will appear after choosing this option).

Enter (or select from the drop-down list) the antennas diameters (and antenna gain, in case of using “Other” antennas). The options are the following: 0.3; 0.6; 1.2; 1.8; 2.4; 3; L250 range if “Comhat-Provexa” antennas are used, or 0.3; 0.6; 0.8; 1.2; 1.8; 2; 2.4; 3 if “DG antennas” or “Other” option was selected from the “Choose type of antenna” drop-down list. In case of using two antennas there will be two rows intended for antenna data input, in case of using four antennas the additional rows for “Antenna A FD” and “Antenna B FD” will appear.

Main frequency

Enter the main frequency in GHz.

Diversity frequency

Enter the diversity frequency in GHz.

Losses



This cell will contain the calculated received signal level in dBm.

Fade Margin

These two cells will contain the calculated fade margin values corresponding to the particular BER level (10-3 and 10-6).





Rain Availability The cells under this heading will represent the calculated link availability (%) in rain conditions at particular BER levels (10-3 and 10-6 respectively) for both vertical and horizontal antenna polarization.

Multipath+Rain Availability The cells under this heading will represent the calculated aggregate multipath and rain availability (%) at particular BER levels (10-3 and 10-6 respectively) for both vertical and horizontal antenna polarization.

2.9 Rain Zone The Rain Zone work sheet (Fig. 9) is intended for determining the respective amount of precipitation in equipment installation area. This work sheet represents the world map with precipitation indexes (in mm/h, exceeded for 0.01% of the average year) shown on it.

Fig. 9. Source: ITU-R P.837-4 "Characteristics of precipitation for propagation modelling".

3 References ITU-R P.453-9 "The radio refractive index: its formula and refractivity data"

ITU-R P.835-3 "Reference standard atmospheres"

ITU-R P 530-11 "Propagation data and prediction methods required for the design of terrestrial line-of-sight systems"

ITU-R P.837-4 "Characteristics of precipitation for propagation modelling"

ITU-R P.676-5 "Attenuation by atmospheric gases"

4 SAF Tehnika Contacts Most up to date contacts of SAF Tehnika A/S could be found at Web site www.saftehnika.com.

SAF Tehnika A/S technical support could be reached at:

Email: [email protected]

Telephone: +371 7046840

Fax: +371 7046809


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