Skip to main content
Search type Search syntax
Tags [tag]
Exact "words here"
Author user:1234
user:me (yours)
Score score:3 (3+)
score:0 (none)
Answers answers:3 (3+)
answers:0 (none)
isaccepted:yes
hasaccepted:no
inquestion:1234
Views views:250
Code code:"if (foo != bar)"
Sections title:apples
body:"apples oranges"
URL url:"*.example.com"
Saves in:saves
Status closed:yes
duplicate:no
migrated:no
wiki:no
Types is:question
is:answer
Exclude -[tag]
-apples
For more details on advanced search visit our help page
Results tagged with
Search options answers only not deleted user 235

BPSK, a mechanism of modulation is expanded Binary Phase Shift Keying.

3 votes

Prevent negative image with BPSK modulation in a complex signal

An actual BPSK signal can be expressed as $$\begin{align} s(t) &= \operatorname{Re}\left[\sum_{n=-\infty}^\infty (-1)^{b_n}p(t-nT)e^{j(2\pi f_c t + \theta)}\right]\\ &= \left[\sum_{n=-\infty}^\infty (- … and say that $$\sum_{n=-\infty}^\infty (-1)^{b_n}p(t-nT)e^{j(2\pi f_c t + \theta)}$$ is a BPSK signal containing positive frequencies only. …
Dilip Sarwate's user avatar
3 votes
Accepted

Prevent negative image with BPSK modulation in a complex signal

output to leave only one BPSK signal. … If one desires to have only the BPSK signal at $f_1+f_0 = f_c$ Hz, say, then the BPSK signal at the image frequency $f_1-f_0$ must be filtered out by passing the mixer output through a bandstop filter …
Dilip Sarwate's user avatar
2 votes
Accepted

DPSK vs PSK Error Probability

Turning to the question of why the trick of using the coherent BPSK error formula as a guide and simply replacing the SNR for BPSK with the SNR for DBPSK in the error probability formula doesn't give the … Note, for example, that $P_e = Q(\sqrt{2E_b/N_0})$ for coherent BPSK but only $Q(\sqrt{E_b/N_0})$ for coherent FSK. …
Dilip Sarwate's user avatar
3 votes
Accepted

BPSK consecutive same symbols

The canonical baseband version of BPSK is that we wish to transmit a sequence $\{a_k\}$ of bits ($0$ or $1$) at a rate of $1$ bit every $T$ seconds using a pulse $g(t)$ of duration $T$ and so the transmitted … $f_c$ is the carrier frequency) and so during $[T,2T)$, the passband BPSK signal is just this passband RF burst delayed in time by $T$ seconds. …
Dilip Sarwate's user avatar
4 votes
Accepted

Bandpass filter BPSK

The mixer/LPF filter that you describe as the receiver is typically one that is designed (possibly for optimal performance e.g. matched filter) using a mathematical model that assumes its input is the …
Dilip Sarwate's user avatar
3 votes

Processing OBPSK as OQPSK

OBPSK in the way that you describe it is also called $\pi/2$-BPSK meaning that the signal constellation is different from bit to bit, rotating by $\pi/2$ after it is used. …
Dilip Sarwate's user avatar
0 votes

mpsk demodulation using digital sample

You are taking 64 samples per second, consisting of 8 samples per period of a sinusoid of frequency 8 Hz. The information that you need to determine is which of the 8 possible phases of the sinusoid y …
Dilip Sarwate's user avatar
3 votes

Deriving the BER equations for BPSK; justification for noise variance of $\frac{N_0}{2}$

The OP's model of white noise as a process with finite power is where the problem is. The standard model of continuous-time white noise that is used in communications and signal processing has infinit …
Dilip Sarwate's user avatar
5 votes
Accepted

How to soft decode DQPSK?

Two successive symbols in the demodulator are $Z_1 = (X_1,Y_1)$ and $Z_2 =(X_2,Y_2)$ where $X$ is the output of the I branch and $Y$ the output of the Q branch of the receiver. The hard-decision DBP …
Dilip Sarwate's user avatar