A microwave link transfers information inelectrical form from one point to another by means of a microwave radio signal. The microwave transmitter accepts a digital data signal input and produces an analog radiofrequency(rf) electromagnetic signal output. The microwave receiver accepts the analog rf electromagnetic signal from the transmitter via the propagation path and produces a digital data signal output. The purpose of the interoperability standards is to standardize the digital data and analog rf electromagnetic signals. The object is to enable microwave links to operate integrally with other microwave links and links that utilize other transmission media within long-haul and tactical communications systems. The purpose of the performance standards is to establish parameters that will ensure that the output digital data signals replicate the input digital data signals.Figure 1 illustrates a typical digital LOS microwave radio link.