Ogier Electronics offers the widest range of microwave transmission solutions for CCTV applications.
Our extensive range allows us to provide the optimum solution to our customers. We have supplied all the above configurations, sometimes with different solutions performing different tasks within the same overall system, e.g. analogue transmission for fixed links and digital for mobiles. Equally, we have provided systems with fibre optic or Wi-Fi equipments from other manufacturers integrated with our own transmission elements.
We are also experienced in the designed and implementation of complete city-wide CCTV systems and have acted as prime contractors on large (multi-city) homeland security projects.
As a result we believe that we are uniquely placed to provide solutions that exactly match our customers' specific requirements.
There are many different options that enable video to be transmitted from the cameras of a CCTV system to the Control Centre. Coaxial cable can be used if the ranges are very short and there is an easy path. Lasers can be used, although they are very vulnerable to weather and require precise alignment with particularly rigid installations. Alternatively fibre optic cable can be employed if it is currently available and it is reasonably secure.
If however no fibre is available, it is invariably cheaper and quicker to use microwave. In some cases it is the only solution. With the Ogier range of products the video quality of the microwave transmission is equal to that available from the best fibre optic systems.
Even if the decision is made to use microwave, there are still many options, the major ones of which are summarised below. A brief summary of the pros and cons is provided with more details given in the Downloads.
Because we manufacture equipment covering the full range, we believe we can give impartial advice on which technology is best suited to each application. The information provided here is intended as an introduction only. If more details or assistance is required, please contact us through the Contact Us page or directly by phone.
All commercial digital transmissions compress the video data, which means that some data or resolution will be lost. In addition time is taken in compressing and decompressing the signal.
This is not necessary with analogue transmission, which means that it is capable of providing the very highest video quality with no latency whatsoever. This makes it particularly applicable to safety critical monitoring systems where delays or loss of quality cannot be accepted, and to long-range camera systems where loss of clarity or resolution could necessitate longer focal length lenses, or to many city centre systems where real time operation is essential for the efficient tracking of targets.
However the major disadvantage of analogue is that it has a very limited non-line of sight capability. Thus in general, the digital links are the only effective solution for mobile or transportable systems where lines of sight cannot be guaranteed.
Digital Video Broadcast - Terrestrial (DVB-T) provides the best video quality of all the digital options together with the most resilience. Thus it is the right solution where video quality is important or where the transmission paths are complex. Its disadvantage is that it generally requires more bandwidth than IP, typically four times as much. This means that our single Ethernet link can transmit 20 IP videos in the same bandwidth as required by 5 DVB-T channels.
The other issue is that DVB-T is a more expensive technology, compounded by the fact that it is essentially a one-way system and therefore requires additional hardware to achieve two-way transmission. Thus if price and camera control are equally or perhaps more important than video quality, an IP solution could well be better. General applications include monitoring overall activity or detecting unusual occurrences rather than obtaining precise identification in commercial premises, car parks and supermarkets. Against this, the DVB-T solution will invariably outperform the IP solution in mobile or similar applications where the lines of sight could be complex.
The higher frequency bands are generally preferred because there is more capacity and less chance of interference than in the more cluttered lower frequency bands. Conversely, the higher frequency 31 and 58 GHz bands are more susceptible to rain fade. Typically the range of a 31 GHz link is up to 10 km in Europe, 15 km in the Middle East but only 5 km in the tropics. The range of the 58 GHz equipment is even shorter because as well as rainfall, oxygen absorbs 94% of the signal every kilometre.
Thus if very long ranges are required, it is necessary to use lower frequencies. The ideal is the 5 GHz band because it is substantially unaffected by weather. It is also generally protected by a licensing regime and therefore has better immunity against interference than the public bands. The ranges of these links can be as long as 100 km for single channel equipment and 80 km for multichannels.
An alternative is to use the licence exempt bands around 2.4 and 5.8 GHz. Although we manufacture such equipment, we do not recommend their use except for very short ranges in cities or in open countryside. The reason for this is that being a public band system, interference is becoming an increasingly serious and sometimes insurmountable problem - see below.
There are three advantages in using the public bands at 2.4 and 5.8 GHz.
The major disadvantage is interference because the band can be used by anyone, including all the wireless laptops, microwave ovens and any of number of ISM systems. It is not an issue in short-range domestic applications, but in CCTV the effects can be serious because the ranges are longer and the video is required continuously.
Licenced bands by comparison require regulatory approval, which enables them to be interference free. In addition, there is up to 10 times the spectrum available, which means that they can accommodate far more cameras with higher data rates and hence better images. Their two disadvantages are the higher cost of the professional rather than domestic equipment and the fact that they do not have an effective non line of sight capability because of the higher frequencies that are employed.
The conclusions are that the licence exempt bands should be avoided for safety critical applications, high security systems, or even when high quality video and interference free operation is essential. Such systems have to use licenced frequencies. Licence exempt frequencies could however be considered for commercial areas or in small housing complexes providing the user is made aware of the possibility of interference. They should not be used in a large or significant citywide system because interference is almost inevitable.
Point-to-Point systems are normally used because the antenna discrimination allows the frequencies to be reused on different cameras. They therefore have higher capacities than Point to Multipoint systems that have to employ a different frequency channel for each camera.
Also the equipment in Point-to-Point systems is simpler if there are few cameras, whereas in Point to Multipoint, a relatively complex Base Station is required irrespective of the number of cameras.
In practice Point to Multipoint is only used in IP based systems. Many companies supply such equipment in the licence exempt bands, whereas we supply equipment in the 10.5 GHz licenced band.
A non line of sight capability is essential for mobile systems. It is also useful in some fixed systems because it can avoid the need for collecting points or relays.
There are however serious limitations. Non line of sight operation requires the signals to be transmitted through objects or reflected off buildings in which 99% of the signal can be lost, which results in a 10:1 reduction in range. This effect is universally true and is irrespective of the modulation used.
The other limitation in using non line of sight is that the characteristics of the paths can well change, which means that one day there may be good communications, whereas on another the communications can be lost. This is a typical problem with Wi-Fi and Wi-Max and whilst not a major problem in domestic applications, it could be serious for professional CCTV systems where it is unrealistic to move the equipment.
In summary therefore mobile systems have to use non line of sight systems. In fixed systems however there is a choice and our recommendation is to use a line of sight system if reasonable ranges and a high availability are required. Alternatively if these requirements are not particularly important it may be possible to use a non line of sight system.
There are several Single Channel link options for analogue video and Ethernet applications.
The SuperCompact comprises a complete transmitter / receiver and antenna in a single unit at each end of the link. It operates in the licenced 31 GHz band, which ensures that the transmission will always be interference free. The equipment has an in-built signal strength indicator for initial alignment, built-in test facilities and remote fault monitoring.
In Europe the SuperCompact transmits video and bi-directional data at ranges of up to 7 km. In the Middle East, where there is less rainfall, the maximum range can be up to 10 km.
The digital data version of the SuperCompact provides Ethernet data rates of up to 50 Mbps over transmission range of up to 8 km. Single hop or multiple repeat configurations are possible.
Ethernet channels can also be installed in our Multichannel Links. Please contact us to discuss project specific requirements.
These units operate within the licence free 58 GHz band, which effectively provides interference immune transmission over short ranges of 600 metres to 1 km due to the high frequencies, narrow beam-widths and uncluttered spectrum.
Like the SuperCompact, all the electronics is contained in a single enclosure at each end of the link. In this case a camera style housing is employed.
The Split Configuration link is able to provide an effective solution when the longest possible range is required on line of sight paths. It comprises a Transceiver and a Base Unit at each end of the link.
The range in all weathers is 25 km at 31 GHz and 100 km or more at 5 GHz. Single or dual channel video streams together with bi-directional data can be transmitted.
The Multichannel link is unique to Ogier Electronics. It can transmit up to 19 real-time, full resolution video channels together with data and audio. Because of this, it is cheaper and easier to install than multiple conventional microwave links. The capacity of the equipment can be increased in service, generally by the addition of plug-in modules.
The equipment is designed for use when multiple video streams need to be transmitted simultaneously over the same path.
A typical application is when several cameras are co-located in a region of a city from which there is no direct path to the Control Centre. In this case Single Channel links transmit to a common Collecting Point from where a Multichannel link transmits to the Control Centre.
As with all our CCTV equipment, the Multichannels can transmit two-way telemetry using all the major protocols, but in addition, it can transmit audio and high speed Ethernet as well.
The range of the 31 GHz equipment is up to 10 km, whereas the long range 5 GHz equipment can transmit up to 80 km.
When there are up to 10 channels, two units are required at each end of the link. A transmit transceiver and a modulator cabinet are installed at the camera end, with a receive transceiver and a demodulator cabinet at the control centre end. The configuration is replicated when more than 10 channels require transmission.
The equipment is quick and easy to install. Two coax cables interconnect the units at either end. All the other external cables terminate in the equipment cabinets.
Using our Broadband Wireless equipment we can create wide area CCTV networks that are capable of transmitting video and data over ranges of 40 km from many hundreds of CCTV cameras to a common Base Station. For further information, please see our Brochure.
The Mobile-T is specifically designed for mobile and transportable applications when there is no clear line of sight from the camera to the Control Centre. The equipment provides broadcast levels of video quality by using the Digital Video Broadcast - Terrestrial (DVB-T) standard with 2,000 carrier OFDM modulation. This enables the Mobile-T to provide the ultimate in transmission integrity in a completely portable package.
The equipment is designed for harsh environments. When fitted to emergency vehicles it can be used to provide near real time video to commanders in the Control Centre. Man pack versions are also available that transmit from hand held cameras to command vehicles. In addition, the system can be used in transportable applications when surveillance is required for a short period to cover specific threats or incidents, or even for sporting or other special events.
The ranges of the man portable equipment are 0.3 to 3 km depending on the line of sight conditions, and 3 to 30 km for vehicle mounted equipment.
A particularly important feature of the Mobile-T is that it can be fully integrated with our static fixed link system to provide citywide coverage using a common infrastructure for both the static and the mobile cameras. In this way continuous coverage can be provided wherever the vehicles are in the city. As the vehicles move from one area to another, the system automatically switches from one collecting point to another. The automatic signal acquisition and handover facility means that the operators can concentrate on their mission, not on operating the equipment. To the best of our knowledge no other company can offer this capability.
The maximum range can be extended to 80 km by relaying the signals from up to 19 co-located vehicles, all transmitting simultaneously.
A summary of the main characteristics of our equipment is provided below. The ranges apply to northern European conditions, but can be doubled for drier environments.
Please click on the equipment name for a PDF file containing the full specification.
|ML3100-30||30cm dish||31 GHz||P2P Fixed||2.5 km|
|ML3100-HP-30||30 cm dish||31 GHz||P2P Fixed||5.0 km|
|ML3100-HP-60||60 cm dish||31 GHz||P2P Fixed||10 km|
|ML500-60||60 cm dish||5 GHz||P2P Fixed||15 km|
|ML500-120||120 cm dish||5 GHz||P2P Fixed||60 km|
|ML3100-SEC||15 cm plate||31 GHz||P2MP Fixed||2 km|
|ML3100-C2||15cm horn||31 GHz||P2P Fixed||2.4 km|
|ML3100-HP-C2||15 cm horn||31 GHz||P2P Fixed||4.5 km|
|ML3100-HP-2-30||30 cm dish||31 GHz||P2P Fixed||10 km|
|ML3100-HP-2-60||60 cm dish||31 GHz||P2P Fixed||20 km|
|ML500-2-120||120 cm dish||5 GHz||P2P Fixed||15 km|
|ML500-2-60||60 cm dish||4.4 to 5.0 GHz||P2P Fixed||60 km|
|SL3100-30||30cm dish||31 GHz||P2P Fixed||6 km|
|ML3100-HP-30||30 cm dish||31 GHz||P2P Fixed||13 km|
|ML3100-HP-60||60 cm dish||31 GHz||P2P Fixed||25 km|
|ML500-60||60 cm dish||5 GHz||P2P Fixed||20 km|
|ML500-120||120 cm dish||5 GHz||P2P Fixed||80 km|
|SL5800-S||15 cm horn||58 GHz||P2P Fixed||0.6 km|
|SL5800-L||15 cm dish||58 GHz||P2P Fixed||1.0 km|
|SL3100-C||15 cm horn||31 GHz||P2P Fixed||4.5 km|
|SL3100-HP-C||15 cm horn||31 GHz||P2P Fixed||10 km|
|SL3100-SC||15 cm plate||31 GHz||P2P Fixed||5.0 km|
|SL3100-HP-SC||15 cm plate||31 GHz||P2P Fixed||8.0 km|
|Mobile-T Man||various||1 to 6 Ghz||P2MP Mobile||3 km|
|Mobile-T Vehicle||various||1 to 6 Ghz||P2MP Mobile||30 - 60 km|
|TL3100-C||15 cm horn||31 GHz||P2P Transportable||4.5 km|
|TL3100-HP-C||15 cm horn||31 Ghz||P2P Transportable||10 km|
|SL58-C||15 cm plate||5.8 Ghz||P2P Transportable||2 km|
|SL58-HP||15 cm plate||5.8 Ghz||P2P Transportable||10 km|
Ogier Electronics reserve the right to alter this specification without notification.
Our analogue equipment provides the highest possible video quality with no latency. They are truly real-time. All our links carry one or two way telemetry channels for camera control purposes. They can be supplied with modules compatible with the data protocols used in all the major CCTV control systems.
Our digital video links provide broadcast quality by using the Digital Video Broadcast - Terrestrial (DVB-T) standard, similar to that employed by the world's TV broadcasters. They have the lowest possible latency consistent with the need for compression and decompression processing.
Because all our fixed analogue and digital links have the ability to operate in the licenced or protected bands, we can guarantee interference free operation.
Reliability is our foremost priority. All our equipment is designed to the highest professional standards and has been proven for operation in the harshest and in the most rugged of environments. Both military and commercial customers use the same systems.
Careful attention to detail allows the equipment to be used with the highest reliability in some of the hottest to some of the coldest places in the world. It is fully qualified for operation down to -20°C and up to +70°C, and if required, beyond these extremes.
The equipment is subjected to an on-going continuous Reliability Growth programme, a part of which is 100% environmental testing involving temperature cycling during production.