Both, Sine, and RC Phase shift OQPSK, modulation time arrival distributions, shown in Fig.
The variance of the data was worse than for the OQPSK modulation and was comparable to the performance of Semtech module.
The noncoherent OQPSK
demodulator functions as a phase detector.
The behaviors of CRC, bit-to-symbol, symbol-to-chip, and OQPSK
modulator were characterized using Verilog.
To form OQPSK signal in simulation program, it was established the source, generating a random bit sequence of bits.
The BER-to-SNR ratio for OQPSK signal received by classical and modified detectors are shown on diagram (Fig.
8, and demonstrate the ability of the modified PLL to OQPSK detection signal even when signal strength is less than the power of obstacles.
a) becomes impossible to distinguish four different levels of phase, which is typical for OQPSK.
For QPSK, OQPSK
at Net Link Bit Rate R = 1/T, Combining I and Q Channels
The previous works[1,2] confirmed what is generally known to practitioners of OQPSK
signaling: If the signal carrier envelope tends to ripple, then the spectral sidelobe levels at the amplifier output will be proportional to the cube of the signal power at the amplifier input.
A special case of OQPSK
is minimum-shift keying (MSK).
TABLE I NADC AND PCS MOBILE UNIT REQUIREMENTS Standard IS-54/136 IS-95 System NADC/TDMA NADC/CDMA Power +28 +28 out(dBm) Modulation [Pi]/4 - DQPSK OQPSK
Adjacent -26/30 kHz -42/30kHz channel at [+ or -] 30 kHz AT > [+ or -] 900 kHz power (dBc) Alternate channel -45/30kHz -54/30 kHz power (dBc) at [+ or -] 60kHz at > [+ or-] 1.