ece-1109 ECE-1109 Introduction to ECE
1. Guided Media Comparison**
| Feature | Twisted Pair | Coaxial Cable | Optical Fiber |
|---|---|---|---|
| Frequency Range | 0 to 1 MHz | 0 to 500 MHz | 186 to 370 THz |
| Attenuation | High | Moderate | Very low (0.2–0.5 dB/km) |
| Repeater Spacing | ~2 km | 1 to 9 km | ~40 km |
| Bandwidth | Limited (1 MHz) | Medium (500 MHz) | Very high (THz) |
| Data Rate | Up to 100 Mbps | 10–100 Mbps | Hundreds of Gbps |
| EMI Susceptibility | High | Moderate | None (immune) |
| Cost | Lowest | Moderate | Highest |
| Installation | Easiest | Moderate difficulty | Most difficult |
| Weight | Lightest | Moderate | Very light |
| Security | Low | Moderate | High (hard to tap) |
| Crosstalk | High (especially UTP) | Low | None |
| Applications | Telephone networks, LANs (10/100 Mbps) | TV distribution, telephone, LANs | Long-haul, metropolitan trunks, subscriber loops, LANs |
2. Unguided Media (Wireless) Comparison**
| Feature | Radio Wave | Microwave | Infrared |
|---|---|---|---|
| Frequency | 3 kHz - 300 GHz (typically VLF-VHF) | 1 GHz - 300 GHz (UHF, SHF) | 300 GHz - 400 THz |
| Communication Type | Multicast (radio, TV, paging) | Unicast (cellular, satellite, wireless LANs) | Short-range, closed areas |
| Antenna Type | Omnidirectional | Directional (point-to-point line of sight) | Line-of-sight |
| Wall Penetration | Can penetrate walls | Cannot penetrate walls | Cannot penetrate |
| Regulation | Highly regulated | Regulated | Less regulated |
| Distance | Long distance possible | Medium to long (requires line of sight) | Short distance only |
| Bandwidth | Lower | High | Very high |
| Weather Effect | Minimal | Affected by rain, fog | Minimal indoors |
| Applications | Broadcasting, navigation, ship-to-shore | Cellular phones, satellite, radar, TV relay | TV remotes, short-range data transfer, IrDA |