Radionica

22/05/2026

Mosfet explained.

21/05/2026

Basics of Electronics – The Foundation of Innovation ⚡

From understanding Ohm’s Law to exploring Kirchhoff’s Laws, every great engineer starts with strong fundamentals. This visual guide beautifully summarizes key concepts like:

🔹 Voltage, Current & Resistance relationships
🔹 Power calculations simplified
🔹 Resistor & Capacitor networks (Series & Parallel)
🔹 Unit prefixes & basic electrical units
🔹 Alternating Current (AC) fundamentals

As an Electronics & Communication Engineering student, I’ve realized that these “basics” are not just academic—they are the backbone of real-world applications, from circuit design to advanced systems like IoT and embedded solutions.

💡 Whether you're a beginner or revising core concepts, never underestimate the power of fundamentals—they shape your problem-solving mindset.

📌 What concept did you find most challenging when you started electronics?

21/05/2026

Basic PCB Component Placement and Routing Rules

1. No routing is allowed within 1 mm from the PCB board edge and within 1 mm around the mounting holes.

2. Power traces should be as wide as possible and should not be less than 18 mil; signal trace width should not be less than 12 mil; CPU input/output traces should not be less than 10 mil (or 8mil); trace spacing should not be less than 10 mil.

3. Standard vias should not be smaller than 30 mil.

4. Dual in-line package (DIP): pad size 60 mil, hole diameter 40 mil.

🔹 1/4 resistor: 51 × 55 mil (0805 SMD); for through-hole mounting, pad size 62 mil, hole diameter 42 mil.
🔹 Non-polarized capacitor: 51 × 55 mil (0805 SMD); for through-hole mouting, pad size 50 mil, hole diameter 28 mil.

5. Power and ground traces should be arranged in a radial pattern as much as possible, and signal traces should avoid loop routing.

21/05/2026

Capacitors in Real-Life Circuits
Continuing my 21-Day Electronics Learning Challenge - today's focus: how capacitors are actually used in practical applications, beyond textbook theory.
Where capacitors shine in real circuits:
• Power Supply Filtering - smooths voltage and reduces noise
• Coupling - passes AC signals while blocking DC
• Decoupling - stabilizes voltage, especially for ICs
• Timing Circuits - enables delays and oscillators
Real-world examples you've likely used:
• Mobile chargers → stable DC output
Audio systems → cleaner sound with less noise
Microcontrollers → reliable operation thanks to decoupling
capacitors
Key insight:
Capacitors may be small, but they're essential for building circuits that are reliable, efficient, and noise-free.
Moving from storing charge to improving performance - understanding how components work in real applications makes all the difference.

21/05/2026

Many engineers notice the flat region in a MOSFET gate waveform, but don't fully understand what is actually happening there.
That flat region is called the Miller Plateau.
At first glance, it looks strange:
The gate driver is still supplying current, yet gs suddenly stops rising for a short time.
Why?
Because the gate current is no longer mainly charging Cgs.
Once the MOSFET begins to turn on and Vds starts falling rapidly, a large portion of the gate current is redirected into the Miller capacitance (Cga).
In other words:
the gate current is now being used to support the drain voltage transition instead of increasing Vgs.
This is why the gate voltage appears "stuck" temporarily.
And this is not just a waveform detail.
The Miller Plateau directly affects switching speed and switching loss.
A longer Miller Plateau means:
• slower Vds transition
• longer switching time
• more heat generated in the MOSFET
This becomes especially important in high-frequency power designs.
Typical ways to reduce Miller-related switching loss include:
• increasing gate drive current
• optimizing gate resistance
• reducing parasitic inductance
• using soft-switching methods such as ZVS A lot of MOSFET heating problems are actually timing and charge-distribution problems hidden inside a few tens of nanoseconds.

21/05/2026

Why Isolation and ECC Matter in MIMO Antenna Design In modern wireless systems, especially 5G and mmWave communications, achieving high data rates is not just about increasing bandwidth—it also depends heavily on antenna diversity performance.
For MIMO antennas, two critical parameters are:
Isolation (S21)
Isolation indicates how much power from one antenna element couples into another. Poor isolation leads to increased mutual coupling, pattern distortion, and reduced system efficiency.
Typically, higher isolation (e.g., below -20 dB coupling) is preferred for better MIMO performance.
• Envelope Correlation Coefficient (ECC)
ECC measures the correlation between antenna elements.
Lower ECC values indicate better diversity performance and improved channel capacity.
• ECC = O → Excellent diversity
• Higher ECC → Increased correlation and reduced MIMO efficiency
• Why It Matters
High mutual coupling can increase ECC, which may affect practical system behavior such as Rank Indicator (RI), throughput, and spatial multiplexing capability.
• Common Techniques to Improve Isolation & ECC
• Defected Ground Structures (DGS)
• Metamaterial-based decoupling
• Neutralization lines
• Parasitic elements and slot techniques
Currently exploring isolation enhancement techniques for mmWave MIMO antennas to improve overall diversity performance and system reliability.

21/05/2026

Air Surveillance Radar: Key Parameters & Capabilities
Radars are the backbone of modern air defense and situational awareness enabling long-range detection, precision tracking target classification and multi-target engagement in highly dynamic operational environments.
The key parameters and capabilities of air surveillance radar includes:
(a) Detection & Tracking Range
(b) Frequency Band & Bandwidth
(c) Range and Angular Resolution
(d) Doppler Processing & SNR Performance
(e) ECCM Capability & Low Probability of Intercept
(f) Scan Rate, Reliability and Target Capacity Modern radar architectures integrate digital beamforming, adaptive waveform generation and advanced signal processing techniques to achieve superior performance in contested electromagnetic environments.
With advancements in FPGA-based processing, real-time radar signal chains, and network-centric warfare integration, next-generation radar systems are becoming more intelligent, resilient and capable of handling increasingly complex threats across air, land and maritime domains.

19/05/2026

19/05/2026

18/05/2026

18/05/2026

When the Signal Fails, the System Decides: Understanding
UAV Link Degradation
In UAV systems, communication is not just a feature it is the backbone of control, awareness, and navigation.
This illustration highlights a critical reality: different links fail differently, and each failure reshapes system behavior.
S* 1. Control Link Disruption
When the connection between the ground control station and the UAV is degraded, the system doesn't stop it adapts.
Autonomous modes take over:
V Return-to-Home (RTL) V Hover / Position Hold
V Mission Continuation (Fallback Logic)
•Control shifts from human-in-the-loop to system autonomy.
a 2. Video Link Loss
Loss of visual feedback doesn't directly stop the UAV but it impacts the operator:
• Reduced situational awareness
4 Delayed decision-making
A Increased risk of incorrect judgment
• The system flies but confidence drops.
$$ 3. Navigation (GNSS) Degradation
When positioning signals are unreliable:
V Path deviation occurs
V Stability decreases
V Backup estimation (sensor fusion) becomes essential
The UAV is still airborne but navigation integrity is
compromised.
Key Engineering Insight
A UAV is not defined by a single link but by how it responds to failure across multiple layers.
Signal degradation doesn't necessarily stop the system... it
changes who or what is in control.

This is why modern UAV design emphasizes:
V Redundancy
V Sensor fusion
V Robust control algorithms
Because resilience is not about avoiding failure it's about managing it intelligently.