calcPort
========
```{function}  calcPort( port, SimDir, f, varargin)
```
Full definition:
```{code-block} matlab
[port] = calcPort( port, SimDir, f, varargin)
```

Calculate:
  - voltages and currents
  - the propagation constant and the characteristic impedance (if applicable)

The port has to be created by e.g. AddMSLPort(), AddLumpedPort() or AddCurvePort

input:
- port:       return value of AddMSLPort()
- SimDir:     directory, where the simulation files are
- f:          frequency vector for DFT

variable input:
- 'RefImpedance':    use a given reference impedance to calculate inc and
                     ref voltages and currents
                     default is given port or calculated line impedance
- 'RefPlaneShift': for transmission lines only, See also calcTLPort for
                   more details
- 'SwitchDirection': 0/1, switch assumed direction of propagation
- 'SignalType':    'pulse' (default) or 'periodic'

output: 
  - output signals/values in time domain (TD):
    - port.ut.tot:    total voltage (time-domain)
    - port.ut.time:   voltage time vector
    - port.it.tot:    total current (time-domain)
    - port.it.time:   current time vector

  - output signals/values in frequency domain (FD):
    - port.f:                 the given frequency fector
    - port.uf.tot/inc/ref:    total, incoming and reflected voltage
    - port.if.tot/inc/ref:    total, incoming and reflected current
    - port.ZL_ref:            used reference impedance

    - port.P_inc:             incoming power
    - port.P_ref:             reflected power
    - port.P_acc:             accepted power (incoming minus reflected,
                              may be negative for passive ports)

  - if port is a transmission line port:
    - port.beta:              propagation constant
    - port.ZL:                characteristic line impedance

example:

    port = calcPort(port, Sim_Path, f, 'RefImpedance', 50);



-----------------------
(C) 2012 Thorsten Liebig <thorsten.liebig@gmx.de>

See also AddMSLPort, AddLumpedPort, AddCurvePort, calcTLPort, calcLumpedPort