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What's wrong with 180 degree phase shift in QPSK?

OQPSK is used specifically to limit the peak-avg ratio of the QPSK waveform, as it avoids transitions from going through the origin. When the modulation in QPSK changes from one point in the ...
Dan Boschen's user avatar
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Implementing an SDR using C++

I'm a little unclear on the actual hardware. Are you using the zedboard to talk to an SDR, or are you trying to implement an SDR in the zedboard? I.E., where are the RF front ends, local oscillators, ...
njudell's user avatar
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BPSK decoding with a non-ideal transmission medium

It is not typical to transmit rectangular pulses as it results in a much wider spectrum than is necessary, resulting in poor spectrum efficiency and more susceptibility to group delay distortion ...
Dan Boschen's user avatar
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Regarding SINR (Signal to Interference Plus Noise Ratio) in wireless communication

The received signal should be $$ y=h_1s_1+h_2s_2+w $$ So, SINR is to be represented as $$ SINR=\frac{|h_1|^2P_1}{|h_2|^2P_2+N_w} $$
Brijesh Kumbhani's user avatar
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instantaneous frequency for a complex signal

This line [f]=instfreq(lfm); should be [f]=instfreq(lfm)*fs; If I do that and plot the true $\phi$ and the estimated $\phi$ ...
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Why is my Hard Decision Decoding of Convolutional codes not performing well?

Are you accounting for quantization noise in your calculation of the bound when decoding with HDD? One-bit representation is a special case anyway, but the quantization noise has an impact, generally. ...
vml's user avatar
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1 vote

Spreading sequence for dsss or cdma

Why is this type of sequence never used? Complex spreading sequences are used all over the place: OFDMA is a special case of CDMA, for example.
Marcus Müller's user avatar
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A question of channel capacity in precoding case

Your equation is correct, i.e. $\log\det(I+F^*H^*HF)=\log\det(I+H^*H)$. However, the conclusion that unitary precoding doesn't change the capacity of a MIMO channel is not true, in general. It is, ...
syeh_106's user avatar
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