... and distal ring back test function, convenient troubleshooting;5. Channel selection, modulation mode QPSK or 16QAM, ... 8E1/16E1/24E1/32E1Occupied bandwidth (MHz)3.5/7/14/28Modulation typeQPSK/16QAMTransceiver frequencymeta-stable(ppm ... × 265ODU:265×265×110Weight (kg)IDU:3.5 ODU:5.5Work environment indexWorking temperatureIDU:0~+50°C ODU: ... All-weatherAltitude (m)≤4500 Digital microwave transmission system