Design and construction of radio relay lines (RRL)

Radio relay lines are used for information circuit development. Currently, radio relay lines are in great demand. Suffice it to say that major part of transport network of any mobile operator is created with the use of RRL.

The first step in radio relay lines design is the specification of optimal route lines. After all, the construction and maintenance cost of prospective RRL depends on the route choice. All the possible variants of the route are charted, then estimated. The task is to define the necessary quantity of stations and optimal height of antenna mounting for each station in order to ensure specified communication stability. At that the most preferable variant involves minimal heights of antenna mount and maximal average span length, alongside with least possible stations enabled the majority of which are situated in settlements with well developed communications.

Present-day line-of-sight RRL work with the frequency band 0,5-60 GHz. This band ensures large line capacity alongside with high interference stability, owing to which necessary communication reliability is secured. Besides, there are other factors that influence quality of communication channels: haul, route radio-wave propagation, equipment electrical specification, etc. RRL design and construction involves estimation of all these factors.

Having accomplished the stage of estimation, the "RRC" experts coordinate their activity with the customer. The customer is provided with the design and is free to make comments. Later, having matched the positions, the plot situation is corrected, additional calculations are carried out, and the corrected design is re-coordinated with the customer. Constant intercourse with the customer ensures opportune corrections and, finally, more suitable result.

When the route is preliminary selected by the chart, then suitable plots in the area are searched for afield. Such factors as soil properties, electric power supply, relief, top height, high-level irregularity are taken into account. It stands to reason that in actual practice one cannot enable all the plots registered in preliminary design. This explains necessary adjustments in the course of site works.

Every chosen plot undergoes the construction permits formalities. The contract relations with landowners and owners of existing property are registered as well. RRL are formed of terminal stations and intermediate repeaters. RRL interval length ranges from some hundred meters to forty-seventy kilometers. Information input and output are carried out on terminal stations, while intermediate repeaters work as signal-wave transponders. Communications reliability in the intervals, as well as RRL facilities operational safety and quality of service are vital issues that form the general RRL reliability. The initial design stage should provide a solid base by choosing the right plots to fulfill these demands in production period.

Having selected the plots, the "RRC" experts run site and topographical survey for the antenna support construction. Besides, this stage involves technology definition, as well as preparing working and design construction documents. The validation is then followed by the construction.

"RRC" and RRL construction

In the course of work "RRC" faces many design and construction issues. "RRC" has designed and constructed thousands of RRL intervals. Besides, "RRC" has experience of RRL design and construction for large-scale enterprise communication demand and installations of telephones in settlements.

These are just few "RRC" projects:

• Installation of telephones in Chernogolovka and Selyatino settlement (Moscow region). "RRC" has fulfilled all the work, from frequency receipt, design and construction, to execution of title documents;
• Mounting and commissioning of the RRL "MINI LINK" equipment produced by "ERICSSON" in the interests of "Sky Link";
• Mounting and commissioning of the RRL "PASOLINK" equipment produced by "NEC", as well as the RRL "INTRA LINK" equipment in the interests of "МТS";
• Mounting and commissioning of the RRL "PASOLINK NEO" equipment produced by "NEC" for the "Bystrinskneft" PGEA objects (Petroleum and Gas Extracting Administration) in the interests of "T-Helper Svyaz";
• Mounting and commissioning of the RRL "DMR 5000" equipment produced by "NEC" for the ESPO (Eastern Siberia-Pacific Ocean) Oil Pipeline objects under the agreement with "Svyaztransneft" in the interests of "Transneft".