TABLE OF CONTENTS A standard (all indoor) microwave radio configuration consists of the entire microwave and digital modem part being placed indoors, the microwave antenna mounted outside on the tower, and a waveguide connecting the radio transceiver with the antenna. Today, the most commonly used waveguides for terrestrial microwave point-to-point systems are elliptical waveguides. This solution is acceptable for the lower frequencies, below 10 GHz, and high-capacity (backbone) microwave systems, but it quickly becomes unacceptable as frequency in-creases. This a result of the losses in transmission lines (coax or waveguide), which become unacceptably high at higher frequencies.
Whenever possible, split configuration microwave radio is replacing the standard configuration. To reduce losses between the transceiver and antenna, the outdoor unit (ODU) containing all of the RF modules can be mounted near the antenna. The ODU is connected to the indoor unit (IDU), which contains baseband circuitry, modulator, and demodulator, by means of a single coaxial IF cable. The distance between the indoor and outdoor equipment can usually be up to 300 m.
The equipment operates from a battery supply between -40.5 and -57 V, nominally -48 VDC. The primary DC power is supplied to the indoor unit through a main fuse and a filtering function, which includes input filter to attenuate the common mode noise. The power to the outdoor unit is supplied from the indoor unit via the IF coaxial cable.
Transmit output power...
