Ogier DL10 offers a cost effective solution for rural areas where ADSL or cable is neither available nor financially viable. The system operates in the 10.5 GHz frequency band and achieves high megabit data rates over ranges up to 10 km.
The system interfaces directly to Data-Over-Cable-Service-Interface-Specification (DOCSIS) equipment (the de facto world standard for IP cable systems).
DL10 allows operators the maximum flexibility in the choice of equipment manufacturers and suppliers. The system is transparent and behaves identically to cable.
Systems have been in operation since 1999 with major cable operators in Brazil, Mexico, Saudi Arabia, Denmark, Ukraine, Spain and Ireland.
The system has been tested successfully with DOCSIS 3 routers and modems.
A key feature is that the system interfaces directly to open standard routers and modems that are in use in almost every country in the world.
Many manufacturers can supply these elements, which means that all their developments are available to the benefit the network. They include upgrades of the DOCSIS specifications, Voice over IP and higher data rate operation.
The equipment has been designed to be simple and straightforward to install.
Should operators so chose, they can undertake all the installation work themselves. Indeed in Denmark, local electricians have installed Base Stations and many subscribers install their own CPEs.
The system is scalable from low data rates as little as 30 Mbps. This means that the infrastructure cost need only be committed when it is needed, which makes it ideally suited to meet the growing needs of a developing market.
The growth in capacity, combined with the low cost of the customer premises equipment, a fraction of that of other proprietary systems operating in the licenced bands, means that the system is so inexpensive it is affordable to residential as well as business users.
Financial models of the payback times show that it can compete head-on with fixed line systems, even if the requirement is to recover all the infrastructure costs within 18 months or less.
The system is unique in that it has the capacity and the range to provide the backhaul communications between the primary Base Station and Secondary Hubs, as well as the "last mile" transmission to the subscribers.
The Base Station and the Secondary Hubs have up to four 90 degree sectors for local subscribers, and use the same antennas, transmitters and receivers to provide the backhaul. This arrangement avoids the need for an array of fixed point-to-point microwave links and in so doing, simplifies the complexity, reduces the cost and increases the reliability of the network.
All the commercial operators of the equipment use this unique feature.
Backhaul network deployed by Universal Communications in Belo Horizonte province (Rio de Janeiro) in Brazil.
The base station simply requires a router, an up-converter and a wireless transceiver with its integrated antenna and a power supply unit. A single transceiver covers a 90-degree sector. Thus four transceivers will be required to provide full 360-degree coverage.
Multiple transceivers can be installed in any given sector if the capacity requirements are high in a particular direction.
Conversely, in rural areas where the capacity requirements can be lower, a single transceiver can be used in a slave/master hub configuration to feed two sectors. In this way only two transceivers are required for the full azimuth coverage.
A single router can provide the data processing for up to 8 transceivers serving up to 7,000 subscribers.
The standard DOCSIS CPE (Customer Premises Equipment) comprises a wireless module and a wall plug power supply.
The wireless modules are designed for all weather operation on standard wall mount installations. Line of sight is required to the base station.
The alignment can usually be performed by eye in all but the most critical cases.
A single 75 ohm coaxial cable connects the CPE to the power supply and DOCSIS modem.
There are no radiation hazards to subscribers.
The radiated power is measured at 2,000 times lower than the latest safety specification limits for this class of equipment.
The inherent flexibility of the system is illustrated in multiple dwelling units where a number of options are possible. A separate self-contained system can be supplied for each dwelling. Alternatively, a single wireless can feed a separate modem for each subscriber without any loss of capability from a stand-alone system.
Yet another option is to feed an Ethernet output from the Cable Modem through a switch to all the users. In this case however the total data rate will have to be shared by all the users.
Only in exceptional circumstances will there be a line of sight from the base station to all the subscribers. Even if the terrain is flat, buildings and trees can obscure the signal. Typically there is often only a 60% probability of a line of sight. Repeaters can be utilised to overcome this limitation by providing overlapping coverage from several base stations.
Fitting a larger external antenna to the subscriber units can increase the range of the system. For example a larger 60 cm antenna option increases the range up to 25 km whilst maintaining 99.99% availability, even under worst-case northern European conditions.