I once used a GNU Radio QPSK receiver for oQPSK demodulation. All I did was to "forcefully" delay the Q channel by half the symbol time. At the time, I was using a discrete number of samples per symbol divisible by 2 (which made it easier to delay the Q channel). I'm now wondering how to achieve the same when the number of samples per symbol is neither discrete nor divisible by two. Could a fractional interpolator (Cubic, polyphase, etc) be used in this case (i.e. to delay the Q channel by N/2)?