I'm looking at the thermal specs for the HMC641ALC4 and need some help with clarification of the parameters. On page 3 of the HMC641 data sheet it shows the following:

Thermal Resistance Channel to die bottom

Insertion Loss Path  201 °C/W 

Terminated Path 321 °C/W

My questions are:

1.) Is the Insertion Loss Path  201 °C/W  = to the path straight through the device?

2.) Is the Terminated Path 321 °C/W  = to the path terminated to the internal resistor?

3.) What is meant by the Channel?

4.) How do I calculate the Die to Case temperature?