i had certain questions regarding the filter section in incremental ADC,
1) what is the significance of using (n+1) order digital filter for n order single feed forward loop modulator instead of using n order filter?
2) in the attached paper, for 2nd order incremental ADC, the second integrator output has been calculated and the term (n-i+1) is derived to cancel the error (page 7 and equation 3). if we have third order single loop incremental ADC, what equation we will get at the output of third integrator?

thanks in advance