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The propagation delay of the XOR gate, AND gate and multiplexer (MUX) in the circuit shown...

  For T= 0,  Delay = (2+1) = 3ns For T= 1 Delay = (2+1) + (2+1) = 6ns For worst case it is 6 ns Answer (c) 6 ns

Advanced Flat vs Frequency-Selective Fading Simulator

Flat vs Frequency-Selective Fading Simulator Flat vs Frequency-Selective Fading Interactive Multipath Channel Simulator Change the channel mode, delay spread, signal bandwidth, Doppler frequency, and SNR. Observe how the channel response changes. Parameters Channel Mode Flat Fading Frequency-Selective Fading Signal Type Pure Sine Wave Wideband Multitone Signal Center Frequency 1.00 MHz Signal Bandwidth 1.00 MHz Maximum Doppler 30 Hz SNR 25 dB Reflected Path Power -3 dB Maximum Path Delay 2.0 μs Number of Paths 4 Run Simulation Channel -- Signal BW -- Coherence BW -- RMS Delay Spread -- 1. Transmitted Signal 2. Channel Impulse Response 3. Channel Frequency Response 4. Received Signal 5. Signal Spectrum 6. Received Envelope 7. Doppler ...

The electrical system shown in the figure converts input source current is(t) to output voltage v0(t)...

  1. At node X The source current i s ( t ) i_s(t) splits into capacitor current and resistor current: i s ( t ) = i C ( t ) + i R ( t ) i_s(t)=i_C(t)+i_R(t) For the capacitor, i C = C d v C d t = d v C d t i_C=C\frac{dv_C}{dt} =\frac{dv_C}{dt} because C = 1 F C=1F . For the 1 Ω 1\Omega resistor, i R = v C 1 = v C i_R=\frac{v_C}{1}=v_C Therefore, i s = d v C d t + v C i_s=\frac{dv_C}{dt}+v_C so v ˙ C = i s − v C \boxed{\dot v_C=i_s-v_C} This gives the second state equation. 2. For the inductor branch The inductor 1 H 1H and resistor 1 Ω 1\Omega are parallel . Therefore, they have the same voltage . For the inductor, v L = L d i L d t v_L=L\frac{di_L}{dt} Since L = 1 H L=1H , v L = d i L d t v_L=\frac{di_L}{dt} For the parallel 1 Ω 1\Omega resistor, v R = i R v_R=i_R Since their voltages are equal, d i L d t = i R \frac{di_L}{dt}=i_R Now the source current splits between the inductor and resistor: i s = i L + i R i_s=i_L+i_R Therefore, i R = i s − i L i_R=i_s-i_L Hence, i ˙ L =...

How Hilbert Cancells SSB Sideband

Start with a simple baseband tone Take m ( t ) = cos ⁡ ( ω m t ) m(t)=\cos(\omega_m t) and carrier cos ⁡ ( ω c t ) . \cos(\omega_c t). If we simply multiply them: s ( t ) = m ( t ) cos ⁡ ( ω c t ) s(t)=m(t)\cos(\omega_ct) then s ( t ) = cos ⁡ ( ω m t ) cos ⁡ ( ω c t ) . s(t)=\cos(\omega_mt)\cos(\omega_ct). Using cos ⁡ A cos ⁡ B = 1 2 [ cos ⁡ ( A + B ) + cos ⁡ ( A − B ) ] , \cos A\cos B =\frac12[\cos(A+B)+\cos(A-B)], we get s ( t ) = 1 2 cos ⁡ ( ( ω c + ω m ) t ) + 1 2 cos ⁡ ( ( ω c − ω m ) t ) \boxed{s(t)=\frac12\cos((\omega_c+\omega_m)t)+\frac12\cos((\omega_c-\omega_m)t)} So we get two frequencies : ω c + ω m \boxed{\omega_c+\omega_m} and ω c − ω m . \boxed{\omega_c-\omega_m}. These are the upper sideband (USB) and lower sideband (LSB) . We want only one Suppose we want the upper side...

MATLAB Code for Hilbert Transform

  MATLAB Code clear; close all; clc; %% Parameters Fs = 1000;          % Sampling frequency T  = 2;             % Duration t  = 0:1/Fs:T-1/Fs; fm = 5;             % Message frequency fc = 100;            % Carrier frequency %% Baseband signal m = cos(2*pi*fm*t); %% Hilbert transform mh = imag(hilbert(m)); %% Analytic signal ma = m + 1j*mh; %% Envelope and instantaneous phase envelope = abs(ma); phase = unwrap(angle(ma)); %% I/Q modulation I = m; Q = mh; USB = I .* cos(2*pi*fc*t) ...     - Q .* sin(2*pi*fc*t); LSB = I .* cos(2*pi*fc*t) ...     + Q .* sin(2*pi*fc*t); %% Ordinary DSB-SC DSB = m .* cos(2*pi*fc*t); %% Plot everything figure('Color','w'); subplot(4,2,1) plot(t,m,'b') grid on title('Baseband m(t)') xlabel('Time (s)') subplot(4,2,2) plot(t,mh,'r') grid on title('Hilbert transform m̂(t)') xlabel('Time (s)') subplot(4,2,3)...

Interactive Hilbert Transform Simulator

  Hilbert Transform & I/Q Simulator Hilbert Transform / Analytic Signal / I-Q Simulator Message frequency Carrier frequency Sampling frequency Duration Run simulation 1. Hilbert Transform m(t) = cos(2π fₘ t) m̂(t) = Hilbert{m(t)} 2. Analytic Signal mₐ(t) = m(t) + j m̂(t) Envelope = |mₐ(t)| 3. I/Q Modulation s(t) = I(t)cos(ωₙt) − Q(t)sin(ωₙt) I(t) = m(t) Q(t) = m̂(t) 4. SSB USB = m(t)cos(ωₙt) − m̂(t)sin(ωₙt) LSB = m(t)cos(ωₙt) + m̂(t)sin(ωₙt) 5. Frequency Domain Return to Premium Virtual DSP Lab →

Hilbert Transform Explained

The Hilbert transform of a signal x ( t ) is x ^ ( t ) = H { x ( t ) } = 1 π PV ∫ − ∞ ∞ x ( τ ) t − τ d τ \boxed{\hat{x}(t)=\mathcal H\{x(t)\} =\frac{1}{\pi}\operatorname{PV}\int_{-\infty}^{\infty} \frac{x(\tau)}{t-\tau}\,d\tau} where PV means the Cauchy principal value , because the kernel 1 t − τ is singular at τ = t . Convolving a time-domain signal f ( t ) f(t) with the Hilbert transform kernel 1 π t \frac{1}{\pi t} pro...


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