Skip to main content

Comparisons among ASK, PSK, and FSK (with MATLAB + Simulator)


Comparisons among ASK, PSK, and FSK

Comparison among ASK, FSK, and PSK
Parameters ASK FSK PSK
Variable Characteristics Amplitude Frequency Phase
Bandwidth The minimum theoretical bandwidth for BASK is equal to the bit rate, Nb. The bandwidth requirement is approximately (fc2 - fc1) + Nb. The bandwidth is always greater than ASK. The minimum theoretical bandwidth for BPSK is equal to the bit rate, Nb. It is more bandwidth-efficient than FSK.
Noise Immunity Poor. Amplitude is highly susceptible to noise interference. Good. Less affected by noise than ASK as information is in frequency, not amplitude. Excellent. Offers the best noise immunity of the three for the same signal power.
Complexity Simple to implement. More complex than ASK. Most complex, as it requires a phase-synchronous (coherent) detector.

Comparison of Performance

Feature ASK (OOK) BFSK BPSK
Power Efficiency Low Medium High
Bandwidth Efficiency High Low High
Noise Immunity Poor (Sensitive to Amp) Good Excellent
Best Used In Fiber Optics, RFID Caller ID, Paging Deep Space, Satellite

Simulator for Calculating Bandwidth of ASK, FSK, and PSK

The baud rate represents the number of symbols transmitted per second. Both baud rate and bit rate are same for binary ASK, FSK, and PSK.

Comparison among ASK, FSK, and PSK

Performance Comparison:

1. Noise Sensitivity:

- ASK is the most sensitive to noise due to its reliance on amplitude variations.
- PSK is less sensitive to noise compared to ASK.
- FSK is relatively more robust against noise, making it suitable for noisy environments.

2. Bandwidth Efficiency:

- PSK is the most bandwidth-efficient, requiring less bandwidth than FSK for the same data rate.
- FSK requires wider bandwidth compared to PSK.
- ASK's bandwidth efficiency lies between FSK and PSK.

3. Complexity:

- ASK and FSK are relatively simpler to implement and demodulate.
- Coherent PSK demodulation can be more complex due to carrier synchronization requirements.

4. Fading and Multipath Resilience:

- FSK performs well in fading and multipath scenarios due to its frequency diversity properties.
- PSK can be affected by fading, especially in frequency-selective fading conditions.
- ASK may experience significant performance degradation in fading and multipath channels.

5. Applications:

- ASK is commonly used in simple applications such as remote controls, RFID, and binary communication.
- FSK is suitable for applications where noise immunity is important, such as wireless communication and telemetry systems.
- PSK is widely used in digital communication systems, including modems, Wi-Fi, and digital broadcasting.

The choice of modulation technique depends on the specific requirements of the communication system, including the channel characteristics, noise levels, data rate, and complexity constraints. Each modulation technique has its strengths and weaknesses, and the best choice will depend on balancing these factors for the given scenario.

ASK vs. FSK vs. BPSK: Key Differences

Feature ASK FSK BPSK
Parameter Changed Amplitude Frequency Phase
Noise Immunity Low (Very Sensitive) High Very High
Bandwidth Efficiency High Low High
Complexity Simple Moderate Complex

ASK Applications

  • • Optical Fiber Communications
  • • Infrared Remote Controls
  • • Early Wireless Telegraphy

FSK Applications

  • • Caller ID Systems
  • • Garage Door Openers
  • • Low-speed Radio Modems

BPSK Applications

  • • Deep Space Telemetry
  • • Satellite Communications
  • • GPS Navigation Signals

Graphical or plot representation of ASK, FSK, and PSK

Message Signal

Carrier Signal

ASK Signal

FSK Signal

PSK Signal

The above figures show that the carrier frequency for ASK is 10 Hz. For PSK, that is 5 Hz. But for FSK, carrier frequencies are 10 Hz and 2 Hz

Summary

  • ASK is simple to generate, and it has a less complex circuitry in comparison to FSK and PSK
  • As noise is very sensitive to amplitude so it has poor noise immunity.
  • FSK is less susceptible to errors than ASK
  • FSK is suitable for high-frequency communication as modulation deals with two different high carrier frequencies here.
  • FSK circuitry is moderately complex
  • The bit rate in FSK is higher than in ASK
  • In FSK, noise immunity is high
  • PSK circuitry is very complex
  • PSK has a higher bit rate as compared to FSK
  • PSK has better noise immunity than FSK

Why are ASK, FSK, and PSK used?

Electronic devices are sensitive to amplitude, frequency, and phase, so these three digital modulation techniques are used during wireless data transfer.

Comparison of BER vs SNR among ASK, FSK, and PSK in MATLAB



(Get MATLAB Code)

Fig 2: Comparison of BER vs SNR among ASK, FSK, and PSK

% BER vs SNR Comparison Code Placeholder
% Visit the link above for the full script.
SNR = 0:1:10;
BER_ASK = 0.5*erfc(sqrt(10.^(SNR/10)/4));
semilogy(SNR, BER_ASK);
grid on;
      

Some Questions and Answers (Q&As)

  1. In a coherent Frequency Shift Keying (FSK) system, what is the primary challenge in achieving coherent detection?
    Answer: Maintaining phase synchronization between transmitter and receiver.
    Explanation: Coherent detection requires maintaining phase synchronization to correctly demodulate the signal.
  2. Which of the following is a major disadvantage of Amplitude Shift Keying (ASK)?
    Answer: Susceptibility to noise and interference.
    Explanation: ASK is highly susceptible to noise because it relies on amplitude changes.
  3. Which modulation scheme is typically more bandwidth-efficient?
    Answer: Phase Shift Keying (PSK).
    Explanation: PSK is more bandwidth-efficient because it encodes information in phase shifts.
  4. In Phase Shift Keying (PSK), what is the impact of increasing the number of phase states?
    Answer: Higher data rates.
    Explanation: More phase states allow higher data rates as more bits can be encoded per symbol.
  5. Which of the following is a key advantage of using Non-Coherent FSK over Coherent FSK?
    Answer: Simpler receiver design.
    Explanation: Non-Coherent FSK has a simpler receiver design because it does not require phase synchronization.
  6. Why is Phase Shift Keying (PSK) considered more power efficient than Frequency Shift Keying (FSK)?
    Answer: PSK can maintain performance at lower signal-to-noise ratios.
    Explanation: PSK is more power efficient because it can achieve good performance at lower signal-to-noise ratios.
  7. Which characteristic of FSK modulation makes it advantageous for certain applications?
    Answer: Its robustness in high-noise environments.
    Explanation: FSK is robust in noisy environments because the frequency changes are distinct.
  8. What is the primary disadvantage of using higher-order PSK modulation schemes?
    Answer: Increased sensitivity to noise.
    Explanation: Increased sensitivity to noise due to smaller phase differences between symbols.
  9. Which modulation scheme is typically used in radio broadcasting?
    Answer: Frequency Modulation (FM).
    Explanation: FM is commonly used in radio broadcasting due to its robustness to noise.
  10. In a PSK system, what can be used to improve error performance?
    Answer: Using error correction coding.
    Explanation: Error correction coding helps to detect and correct errors, improving performance.
Wireless Communication Main Page > BER vs SNR Main Page > Online Signal Processing Simulations Main Page > Wireless Communication in MATLAB Main Page >


Contact Us

Name

Email *

Message *

Popular Posts

RMS Delay Spread, Excess Delay Spread and Multi-path ...(with MATLAB + Simulator)

📘 Overview of Delay Spread and Multi-path 🧮 Excess Delay spread 🧮 Power delay Profile 🧮 RMS Delay Spread 📚 Further Reading 📂 Other Topics on RMS Delay Spread, Excess Delay ... 🧮 Multipath Components or MPCs 🧮 Online Simulator for Calculating RMS Delay Spread 🧮 Why is there significant multipath in the case of very high frequencies? 🧮 Why RMS Delay Spread is essential for wireless communication? 🧮 Why the Power Delay Profile is essential? 🧮 MATLAB Codes for Calculating Different Types of delay Spreads Delay Spread, Excess Delay Spread, and Multipath (MPCs) The fundamental distinction between wireless and wired connections is that in wireless connections signal reaches at receiver thru multipath signal propagation rather than directed transmission like co-axial cable. Wireless Communication has no set communication path between the transmitter and the receiver. The line...

Online Simulator for ASK, FSK, and PSK Signal Generation

Interactive Digital Signal Processing (DSP) Tutorial and Simulator for ASK, FSK, and BPSK modulation techniques. Try our new Digital Signal Processing Simulator!   •   Interactive ASK, FSK, and BPSK tools updated for 2025. Start Now Digital Modulation Visualizer: ASK, FSK, & BPSK Simulator Learn and visualize binary modulation techniques (ASK, FSK, BPSK) in real-time with adjustable carrier and sampling parameters. Perfect for DSP students and engineers. 📡 ASK Simulator 📶 FSK Simulator 🎚️ BPSK Simulator 📚 More Topics ASK Modulator FSK Modulator BPSK Modulator More Topics 1. ASK (Amplitude Shift Keying) Simulat...

Amplitude Shift Keying (ASK) Modulation & Demodulation (with Simulation)

Amplitude Shift Keying (ASK): Signal Analysis and Characterization Theoretical Overview: Amplitude Shift Keying (ASK) represents a primary digital modulation technique wherein information is encoded through discrete variations in the carrier signal's instantaneous amplitude. In a Binary ASK (BASK) framework, the modulation process maps binary data onto two distinct amplitude levels. Specifically, the binary '1' (mark) is conveyed by a sinusoidal carrier with amplitude A c and frequency f c over a bit interval T b , while the binary '0' (space) is represented by a null signal state. This particular signaling method is widely recognized as On-Off Keying (OOK) . It is technically realized by gating a carrier oscillator with a unipolar baseband sequence, effectively performing a product modulation that shifts the baseband spectrum to the carrier frequency. ASK Transmitter Architecture: ...

Hybrid Beamforming | Page 1

Beamforming Techniques Hybrid Beamforming... Page 1 | Page 2 | Hybrid Beamforming: Hybrid beam formation was developed to address some of the limitations of digital pre-coding approaches. Every antenna element is connected to an RF chain in digital pre-coding (beam forming) method. We also know that each RF chain is in charge of providing a separate data stream between the transmitter and the receiver. We know that a larger number of independent data streams leads to higher data rates. It has a spatial multiplexing feature for MIMO. As a result, we may assume that switching from MIMO to massive MIMO will benefit us more in terms of spatial multiplexing in massive MIMO, where each antenna is coupled to a single RF chain. We'll proceed with a definition of hybrid beam forming. Overview of hybrid beam forming with example: Unlike digital beam forming, more than one antenna element is connected to a single RF chain in hybr...

Frequency Shift Keying (FSK) Modulation & Demodulation (with Simulation)

Frequency Shift Keying (FSK) Theoretical Foundations: Frequency Shift Keying (FSK) is a discrete frequency modulation scheme wherein the digital information is encoded via instantaneous shifts in the carrier signal's frequency. The fundamental implementation is Binary FSK (BFSK), which maps binary data onto two distinct, discrete spectral states. A binary '1' (the "mark" state) is represented by a carrier frequency \( f_1 \), while a binary '0' (the "space" state) corresponds to frequency \( f_2 \). Each symbol is sustained for a bit interval denoted by \( T_b \). FSK Transmitter Characterization: The mathematical model for the modulated BFSK output \( s(t) \) is defined as: \[ s(t) = \begin{cases} A_c \cos(2\pi f_1 t), & \text{for } m = 1 \\ A_c \cos(2\pi f_2 t), & \text{for } m = 0 \end{cases} \] ...

Constellation Diagrams of ASK, PSK, and FSK (with MATLAB Code + Simulator)

Constellation Diagrams: ASK, FSK, and PSK Comprehensive guide to signal space representation, including interactive simulators and MATLAB implementations. 📘 Overview 🧮 Simulator ⚖️ Theory 📈 Q-function 📚 Resources BASK Modulation Transmits one of two signals: 0 or $\sqrt{E_b}$, representing binary 0 and 1. Simple but sensitive to noise. BFSK Modulation Transmits one of two signals: $\sqrt{E_b}$ on the Y-axis or $\sqrt{E_b}$ on the X-axis. These are orthogonal signals. BPSK Modulation Transmits $+\sqrt{E_b}$ or $-\sqrt{E_b}$ (antipodal signaling). Most efficient binary scheme. ...

Coherence Bandwidth and Coherence Time (with MATLAB + Simulator)

🧮 Coherence Bandwidth 🧮 Coherence Time 🧮 MATLAB Code s 📚 Further Reading For Doppler Delay or Multi-path Delay Coherence time T coh ∝ 1 / v max (For slow fading, coherence time T coh is greater than the signaling interval.) Coherence bandwidth W coh ∝ 1 / Ï„ max (For frequency-flat fading, coherence bandwidth W coh is greater than the signaling bandwidth.) Where: T coh = coherence time W coh = coherence bandwidth v max = maximum Doppler frequency (or maximum Doppler shift) Ï„ max = maximum excess delay (maximum time delay spread) Notes: The notation v max −1 and Ï„ max −1 indicate inverse proportionality. Doppler spread refers to the range of frequency shifts caused by relative motion, determining T coh . Delay spread (or multipath delay spread) determines W coh . Frequency-flat fading occurs when W coh is greater than the signaling bandwidth. Coherence Bandwidth Coherence bandwidth is...

UGC NET Electronic Science Previous Year Question Papers with Solutions

Home / Engineering & Other Exams / UGC NET 2026 PYQ ⬇️ Download Papers and Solutions 📋 Exam Pattern 💡 Preparation Tips ❓ FAQs 📊 Exam Highlights: Electronic Science (88) Feature Details Junior Research Fellowship (JRF) ₹37,000 + HRA per month Eligibility M.Sc/M.Tech in Electronics (55%) Validity of Certificate JRF (3 Years) | Lectureship (Lifetime) 📥 Download UGC NET Electronics PDFs Complete collection of previous year question papers, answer keys and explanations for Subject Code 88. Start Downloading 📂 View All Question Papers June 2025 - Question Paper Download PDF June 2025 - Solved Paper + Explanation ...