Power rating of multi-channel linear amplifiers

The requirement for a flexible and transparent method for amplifying multi-channel signals in radio base-stations has led to the development of broadband linear amplifiers. These allow much more flexible frequency planning than a cavity combiner, and much greater power efficiency than a hybrid combiner. Since the multi-carrier amplifier carries a complex signal, which is the sum of all the individually modulated carriers, its peak power rating must be carefully considered. For example, in a 16-channel system the peak rating may be as high as sixteen times the average power (i.e. 256 times the power in each carrier). The authors present an analysis of the peak power of multi-carrier signals, and show that the amplifier power rating may be significantly reduced for a large number of carriers, resulting in reduced hardware and operating costs of multi-carrier transmitters