Half Sine Filter (Custom IQ)
The OQPSK signal from a square to a circle. This eliminates any amplitude variations and turns the OQPSK signal into a constant envelope modulation. The OQPSK now resembles MSK.
filter is used for measurements. The pulse shaping filter changes the vector diagram of anThe equation for the
filter follows. (Tc is equal to the delay between the I and Q portions of the signal. The symbol period is 2Tc.)
The
filter is a standard reference filter in Option BHK.When this filter is selected for OQPSK, the reference constellation points fall on a circle with a magnitude of sqrt(2)/2, but the EVM is still expressed as a percentage of the magnitude of a QPSK symbol point (magnitude = 1). See EVM for more information.
See Also