How CCTV Signal Transmission Works

Once a CCTV camera captures video, that footage has to travel somewhere – usually to a recorder, monitor, or cloud platform.

The way that video gets from point A to point B is called transmission, and it plays a big role in image quality, reliability, and system design.

In this guide, we’ll break down the most common CCTV transmission methods, how they work, and where each one fits best.

Coaxial Cable (Analog CCTV)

Traditional CCTV systems often use coaxial cable (such as RG59) to carry analog video signals. Coaxial transmission is reliable and relatively simple to install.

Typical Max Distance: ~300 meters without amplifiers
Strengths: Simple, durable, budget-friendly
Limitations: Lower resolution (standard-definition analog), signal degradation over long runs

This type of setup is typically paired with DVRs and analog cameras – still common in older buildings and cost-sensitive projects.

UTP (Twisted Pair)

Unshielded Twisted Pair (UTP) cables, like Cat5e or Cat6, are often used with video baluns to transmit analog video signals over longer distances.

Typical Max Distance: 400–600 meters with active baluns
Strengths: Cheaper and lighter than coaxial, flexible installation
Limitations: Susceptible to electromagnetic interference (EMI) without shielding (use shielded twisted pair (STP) in noisy environments)

UTP can also carry power and control signals when paired with appropriate adapters, reducing cabling complexity.

HD-Over-Coax (HDCVI, HDTVI, AHD)

Newer technologies like HDCVI, HDTVI, and AHD allow high-definition video (up to 4K) to be transmitted over existing coaxial cables.

Typical Max Distance: 300–500 meters (depends on resolution and cable quality)
Strengths: Upgrade to HD quality without full rewiring; low latency
Limitations: Still limited by coaxial infrastructure quality; analog video only

This is an ideal solution for sites upgrading from analog systems without replacing all cabling.

IP Transmission (Ethernet/Network Cable)

IP cameras transmit digital video over Ethernet (Cat5e, Cat6) using standard networking protocols like TCP/IP.

Typical Max Distance: 100 meters per Ethernet segment
Strengths: Supports high-resolution (4K and beyond), easy system expansion, remote access
Limitations: Requires good network planning; switches needed for long runs

For distances beyond 100 meters, PoE extenders, switches, or fiber optic links are typically used to maintain network stability.

Many modern installations use shielded Cat6A or even fiber in industrial or high-interference environments.

Power over Ethernet (PoE)

Power over Ethernet (PoE) allows a single Ethernet cable to carry both video data and electrical power to IP cameras.

Standards: IEEE 802.3af (PoE, 15.4W), IEEE 802.3at (PoE+, 30W), IEEE 802.3bt (Hi-PoE, 60–90W)
Strengths: Simplifies cabling, centralized power control, safer installation
Limitations: Power budget must be carefully calculated, especially for PTZ or multi-sensor cameras

PoE is ideal for modern IP CCTV systems, offering cleaner wiring and easier maintenance.

For details on the power side, see CCTV power supply.

Wireless Transmission

Some CCTV systems transmit footage wirelessly, using Wi-Fi, radio frequency (RF), or point-to-point microwave links.

Strengths: Useful where cabling is impractical, such as temporary setups, heritage sites, or remote areas.
Limitations: Wireless systems are prone to signal interference, bandwidth congestion, and latency issues, making them less reliable for high-resolution surveillance.

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Best Practices

Wi-Fi (2.4GHz/5GHz) is convenient but not recommended for critical CCTV systems.
Point-to-point wireless (5GHz or 60GHz) offers greater stability for professional setups.
Encryption (WPA3), firewalls, and network segmentation are essential for secure deployments.

Fiber Optic Transmission

For very long-distance or enterprise-grade CCTV systems, fiber optic transmission is the best choice.

Typical Max Distance: Up to 10–40 kilometers without repeaters
Strengths: Ultra-high bandwidth, no electromagnetic interference (EMI), extremely low signal loss
Limitations: Higher upfront cost; specialized installation skills required

Fiber optics allow multi-building campuses, industrial complexes, airports, and smart cities to connect dozens or hundreds of cameras over vast areas without signal degradation.

Wrapping It Up

Selecting the right transmission method depends on several key factors:

Distance (short vs. long run)
Resolution needs (standard vs. 4K+)
Environment (indoor, outdoor, high-EMI areas)
Budget (cost of cables, switches, converters)
Scalability (need for future expansion)

Many modern CCTV systems blend multiple transmission types – using coaxial in legacy areas and IP or fiber in newly upgraded zones.

Next up: Explore how CCTV systems store recorded footage efficiently and securely.