ã2007г RadioFar
MVDS ( Multipoint Video Distribution System ) is a broadband microwave TV distribution system operating in the 5-40 GHz range.
Taking into consideration propagation conditions, 10,7 – 13,5 Ghz frequency range is deemed as optimal one. Using QPSK modulation
it is possible to implement effective solutions for point-to-point or point-to-multipoint configurations. The major technical advantage of
MVDS technology is a possibility of signal retransmission (up to 3 times from our experience) without regeneration. This is impossible
for MMDS using QAM modulation.By using sector antennas it is possible to obtain a radius of coverage area of up to 40-50km
(depending on terrain details) when transmitting about 10 digital packages. Also it is reasonable to feed MVDS base station signal
into a CATV network (over QPSK – QAM trans modulator).Another advantage of this solution is its cost effectiveness, so it can
be recommended for low budget projects. On a receiving side standard equipment and small size antenna (a reflector diameter
of 25-40cm) is used. At the base station it is used a block converter/ amplifier mounted at the antenna (ODU). Combining signals
is implemented at an intermediate frequency (IDU). The IDU output signal is then sent to the ODU via coaxial cable.The main advantages
can be summarized as follows:
- Possibility of retransmission
- Using standard customer sets (antenna+downconverter)
- Combining signals at intermediate frequency (lack of waveguide path)
- Cost effectiveness
