7- 8 GHz RRL equipment
ã2007г RadioFar
The RRL equipment is intended for building a duplex RRL (reception/ transmission) including four channel
service link that is important for mobile TV stations. It can be powered by 12V source. Broadcast quality of
transmitted signals allows to use this equipment in radio and TV studios.Some modifications differing in
quantity of transmitted TV channels and Input signal format (CVBS or SDI) are available.
Operation principle:
Input signals (video, audio and service) are fed to a modulator. The modulator/coder is a multifunction
device including converter of analog/ composite signals into digital format , then МРЕG2 coder , transport
stream multiplexer + QPSK modulator to 70MHz or satellite tuner IF of 950-2150MHz. The modulator output
signal is fed to a transmitter which shifts the signal to operation frequency of 7-8GHz range. The exact
value of the frequency and an output power (100 … 500 mW) is defined by a customer.The transmitter
output is a waveguide flange or N-type connector or else the transmitter can be combined with antenna
array of 26dB gain in a monoblock. Receiving side equipment is a converter of 7-8GHz into satellite IF
range signal. The converter is a block with waveguide or coaxial input or it can be combined with an
antenna array in a monoblock. A digital DVB-S receiver can be used as a receiver/ When a lead-in cable
length is rather long, IF can be of 70MHz or any other value. For converting IF of 70 MHz in satellite receiver
range it is used an upconverter. A connection distance depends on parabolic antenna size and its quality
(gain-to-noise-temperature). The transmitting and receiving antenna size is chosen when RRL projec
Main technical parameters:
Video channels 2…6
Audio channels (mono) 4…12
Service link channels up to 4
Input video SDI or CVBS PAL
Analogous video nominal level, connector 1V, 75 Ohm, BNC
Video frequency band 6MHz
Input audio nominal level 0 dB
Input Impedance (symmetric input ) 600 Ohm, XLR 3pin
Audio channel frequency band 60 …18000Hz
Signal/noise ratio in operation frequency
range no less 62dB
Nonlinear distortions not more 0,3%
Service link channels:
Service channel frequency band 300 Hz … 7.5KHz
Input Impedance (symmetric input ) 600 Ohm
Input nominal level 0 dB+/-6dB
Output nominal level 0 dB+/-6dB
Signal/noise ratio in operational frequency range -47dB
Nonlinear distortions no more 1,5%
Note: Analogous signal parameters depend on parameters of a receiver you use
Modulator parameters:
Digital format 4:2:0
Compression technique: ISO/IEC 13818 (MPEG-2)
Data rate 6-12 Mb/s
ADC resolution 9 bit
Sampling frequency 13,5MHz
Modulation scheme QPSK, FEC 7/8
Intermediate frequency (IF) 70Mhz or 950...2150
IF level 1mW +/-15%
Radio link frequency band no more 28MHz
Power supply 220V, 50 Hz; +12V on request
Power consumption no more 25W
RF path
Operation frequency (should be chosen
when placing an order) in 7-8 MHz range
Polarization type linear
Output power 100mW ...500mW
Frequency band 28MHz
Distance between the modulator and transmitting equipment (when using RG-6U cable) no more than 100m
Distance between the receiving unit and the receiver (when using RG-6U cable) no more than 50m
The following system can be built based on proposed equipment:
The system provides receiption/transmission of 2 analog video signals (PAL) or 2 digital signals (SDI format),
4 mono or 2 stereo audio and 4 duplex service link channels.
7- 8 GHz RRL equipment
Transceiver appearance
