Defence Technologies Genel Karel Defence

What Is Karel’s SRC-GB Radio Link? Turkey’s Battlefield Data Backbone

On a modern battlefield, the round leaving the barrel matters — but so does the data behind it. The position of a manoeuvring unit, the live feed from a drone, an order from the command post: all of it rides on an invisible spine called the radio link. Turkey’s veteran communications house Karel answers that need with the SRC-GB Digital Radio Link. So what exactly is this system that carries up to two gigabits of data per second through the air, where laying cable is impossible?

What is Karel’s SRC-GB radio link?

The SRC-GB is a digital microwave radio link that carries high-speed data through the air between two points, without any cable. The principle is simple: two antennas with a clear line of sight to each other form a narrow microwave “bridge,” and voice, data and video flow across it simultaneously.

Karel states the system is built for the combat and field environment. In other words, the goal is to establish a durable data backbone in terrain where laying physical cable is either impossible or far too risky — mountain ridges, the forward line, temporary base areas.

What does it do?

Modern warfare is network-centric: every unit, sensor and vehicle is connected, and the physical layer that connects them is very often the radio link. In practice the SRC-GB:

Builds a high-capacity backbone between command posts.
Backhauls the heavy video and data traffic generated by UAVs, radars and surveillance systems.
Extends the link between telephone exchanges, radio gateways and IP networks over long distances.
Provides a rapidly deployable backup path where cabled infrastructure is destroyed or simply absent.

Technical specifications

According to Karel’s official figures, the SRC-GB offers serious capacity:

Feature	Value
Data capacity	1,000 Mbps Ethernet; up to 2,000 Mbps with XPIC
Channel bandwidth	7 / 14 / 28 / 56 / 112 MHz
Modulation	QPSK to 4096 QAM, adaptive (ACM)
Interfaces	Gigabit Ethernet + 10G interface
IDU–ODU link	Single coaxial cable, up to 250 m
Redundancy modes	1+1 HSB Tx, 1+1 FD, 2+0 … 12+0
Frequency bands	ITU-R and CEPT/ERC/REC licensed bands

Two terms are worth unpacking for the non-specialist reader. Adaptive modulation (ACM) means the unit automatically lowers and raises its throughput when weather or interference degrade the path — the link chooses to slow down rather than drop. XPIC (cross-polarization interference cancellation) reuses the same frequency on two separate polarizations to double capacity; this is what takes the SRC-GB from 1 Gbps to 2 Gbps.

Karel’s place in the defence industry

Karel is a Turkish company with roughly 40 years of technology experience that develops its software and hardware in-house. At IDEF 2025 it declared a strategy of “transition to integrated defence technologies,” positioning its exchanges, radio links, radio gateways and flight-display systems under a single communications architecture. Within that architecture, the SRC-GB represents the layer that “moves the data over distance.” Having a domestically developed radio link in the inventory means a national alternative in one of the most strategically sensitive areas of all: the tactical data backbone.

Global rivals and equivalents

Digital microwave radio links are a mature global market. On the civil and military sides, the notable manufacturers, per open sources, include:

Aselsan (Turkey) — domestic military radio-link solutions
Ceragon, SIAE Microelettronica, NEC (Pasolink) — microwave-link specialists
Nokia and Ericsson (MINI-LINK) — telecom infrastructure giants
In tactical/military communications, defence-electronics players such as L3Harris and Thales

The SRC-GB’s 2 Gbps capacity and adaptive modulation place it in the same technical class as modern commercial and military links of this category.

Who uses it, who builds it?

High-capacity radio links are today used as a field backbone by armies and security forces worldwide, NATO nations foremost among them. On the manufacturing side, the US, European, Israeli, Japanese and Turkish firms named above lead the way. A detailed user list for the SRC-GB has not appeared in open sources, but Karel’s positioning indicates the product was developed in line with the requirements of the Turkish Armed Forces.

Export potential

Because it operates in internationally licensed frequency bands such as ITU-R and CEPT/ERC/REC, the SRC-GB is technically compatible with foreign markets. Karel’s stated aim at IDEF 2025 of meeting more than 800 foreign delegates and international partners also signals export appetite. That said, no confirmed export contract or user-nation information for this specific product has appeared in open sources.

Overall assessment

The SRC-GB fills a rarely discussed but indispensable link in Turkey’s network-centric warfare vision: the backbone that keeps data alive at the front. With 2 Gbps capacity, adaptive modulation and high redundancy modes, it ticks the boxes expected of a modern tactical radio link. Its real value, though, lies less in the spec sheet than in being national — a domestic option in an area where dependence on foreign suppliers is the most costly.