Reconfigurable radio frequency distribution network
Introduction
A radio frequency power dividing and phase shifting network, having a single input and a plurality N of output ports, which makes it possible to distribute the input signal on a subset n of the N output ports, in a selective and reconfigurable way, while ensuring matching conditions to all ports. The magnitude and phase control of the output signals is pursued only by varying the phase condition of variable phase shifters present in the circuit.

Technical features
The whole 1xN power dividing and phase shifting network can be divided into two parts:
1) Conditioning network: an 1xN network able to divide the input signal IN into N signals with equal magnitude ij, with j ranging from 1 to N, and suitable phases. 2) Routing network: it is an NxN network capable of dividing each input signal ij into N contributions with equal magnitude, where each contribution in turn is addressed to each of the N output ports. In this way, N contributions, suitably out-of-phased, are combined on each of the N output ports ok (with k from 1 to N) giving rise to constructive / destructive interference and thereby resulting in the distribution of the desired signals. Both network components are based on power dividers, phase shifters and hybrid couplers, ie they do not need switches to route the signals between one port and the other of the circuit (switches that may be present depend on the technology used to implement the variable phase shifters).
Possible Applications
- Beam forming networks;
- Radio localization systems;
- Power amplifiers;
- High-reliability systems;
- Systems with variable gain;
- MIMO systems.
Advantages
- Almost arbitrary control of the magnitude and phase of the output signals;
- Possibility to implement reconfigurable power dividers with both equal and unequal power dividing ratios;
- Possibility to implement reconfigurable baluns;
- High redundancy;
- Modularity.