RF Load Failure Detection Circuit
Original Publication Date: 2002-Oct-02
Included in the Prior Art Database: 2002-Oct-02
RF power combining loads can be large and costly. Their purpose in a coherent combining system is to provide isolation to the other circuits “to be combined”. They also must perform this isolation function in the event one or more of the circuits “to be combined” fails. If the circuits “to be combined” are active devices (e.g. amplifiers), the load must large enough to dissipate up to one half of the RF output power from the remaining amplifier, in the event of an amplifier failure. The reason is, if the load fails, the other amplifier(s) can oscillate (due to unfavorable impedance’s) causing a FCC violation. Figure 1 shows the block diagram of a typical parallel staged amplifier.