Summary: Uplink Power Control Based on Receiver Noise Measurements in Satellite
Naofal AlDhahir John E. Hershey G.J. Saulnier
GE Corporate R &D GE Corporate R &D Rensselaer Polytechnic Institute
Schenectady, NY 12301 Schenectady, NY 12301 Troy, NY 12180
This letter describes a novel procedure for uplink power control in a multicarrier satellite communication
system. The purpose of uplink power control is to compensate for rain attenuation so that all carriers are
at the same power level at the input of the satellite nonlinear amplifier. The presence and amount of rain
attenuation is predicted by continuous monitoring of the receiver noise power.
Attractive features of the proposed scheme include its conceptual simplicity, ease of implementation,
applicability to a wide variety of scenarios, and avoidance of the undesirable overhead, coordination, and
delay requirements associated with previously--used methods.
Power control is essential for achieving high reliability and making optimum use of the available capacity
of multicarrier satellite communication systems. It is desirable to have equal--power carriers at the input
of the satellite's travelling--wave tube (TWT) amplifier, otherwise power disparities among the carriers are
exacerbated by the TWT's nonlinearity resulting in higher inter--modulation distortion (IMD) and loss of
capacity due to wasted power.
Several factors contribute to the disruption of the flat power distribution among carriers, the most im