Noise in Time Interleaved and Double Sampling Circuits

[naalald]

Suppose we have a time interleaved system (e.g. ADC) with two channels, which means the input samples are used by each channel every other one. What would the total noise of the system be? Is it going to be the sum of the noises of the channels or not?
The same question arises in double sampling circuits.
If you have any references regarding this issue please let me know.

 

[allanvv]

Articles about the effect of aperture uncertainty will be relevant as you must ensure the devices receive accurate staggered clocks.