SysCalc provides a variety of components each having a rich set of parameters. To aid in the modeling process, the following guidelines are provided for various devices and structures. In general, there are two basic categories: passive and solid-state based structures.
Passive Structures
For elements falling into this category (e.g., resistive pads and splitters, filters, switches, etc.) the following guidelines should be used:
NF = the structure loss
Gain = the negative of the structure loss
All other parameters can be disabled or set as appropriate.
Example: A 3 dB pad would have the following field entries
NF = 3
Gain = -3
Solid-state based Structures
Lossy Structures
The difference between passive structures and lossy solid-state structures is the inherent non-linearities of the latter — they will both compress and create intermodulation products. Such devices include mixers, active attenuators, diode-based phase shifters, etc. Normally the noise figure and gain would be the same for passive structures, unless the manufacturer’s data sheets say otherwise; however, OIPx (IIPx), OP1dB (IP1dB) and Psat will be realistic values either specified in the data sheets or empirically determined.
Discrete and MMIC amplifiers
In most cases the manufacturer provides the noise figure, gain, OP1dB (IP1dB) and intermodulation performance of its devices in graphical and/or tabular form. Unless you intend to make your own quantitative measurements, the published data should be adequate.