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Xirio allows to configure some link specific parameters in a microwave digital radio link calculation for the fixed service:


Digital hop type. It is possible to select the path type to which a digital hop belongs depending on the network technology and the section type. Through this selection and the calculated distance between the link ends , Xirio proposes by default the quality and unavailability objectives marked by recommendations. It is also possible to define the objectives manually with the option "User defined".


Objectives. For each of the radio equipment modulations different objectives can be set. These are determined by:

oName, Modulation and Mode: uneditable fields, automatically filled in with radio equipment parameters.

oQuality Objective and Unavailability, in percentage.

oEnds Attenuation:  Manual attenuation PSTN to be applied at each end, in dB.

oGuaranteed, which forces automatic frequencies allocation to ensure modulation correct operation

oActive, indicating if modulation will be contemplated in calculations.

oAutomatic objectives calculation, taking into account the selected configuration and distance between ends.


Protection Method. In order to improve digital radio link unavailability, some redundancy can be established in the equipment. Xirio allows the user to establish an N + r protection configuration with or without priority channel. This nominal equipment N-mode mode is available, which means working, and r redundant equipment, waiting for any fault in the main equipment. In case the radio link uses protection, the composition type can be determined, if they work at the same frequency (Iso Frequency), if they use different frequencies (Straight Frequency) or if they use XPIC (same frequency and cross polarization).


Diversity. Diversity techniques allow to improve the received signal level and the signal error characteristic. Xirio allows user to choose the diversity type to apply to the link:

oSpace diversity. Two radio paths are available by having two receiving antennas vertically separated by several wavelengths. To use this option it will be necessary to configure an auxiliary antenna at one of the ends.

oFrequency diversity. A double transmission / reception is available at different frequencies, so that when one fades (phase opposition), the other one reception is effected in phase. It is necessary to define frequency deviation, usually between 2% and 5%.

oAngle diversity. Antennas with more than two beams separated by small angles in vertical plane or antennas pointing with different angles are used. It is necessary to define antennas angular separation and the terrain's refractivity gradient (ITU-R Rec. 453).

oSpace and frequency diversity (two receivers).

oSpace and frequency diversity (four receivers).

oAnti-reflective mechanism. it is possible to cancel a reflection using a second receiving antenna (auxiliary antenna) with a specific separation to the main antenna. To use this option it will be necessary to configure an auxiliary antenna at one of the ends.