Orbital manufactures some of the industry’s highest quality block downconverters (BDCs) for satellite communications. Our BDCs are available in a wide range of bandwidths, frequencies and connector configurations  and can be custom-mounted as required. These frequency converters work with your low noise amplifier (LNA) to provide simultaneous reception of an entire satellite band.

Many of the world’s best SATCOM system integrators use Orbital C, X, Ku and Ka-band BDC modules at their core. Each unit is expertly engineered, hand-tuned and tested – and offers guaranteed performance, stability and long-term reliability in the smallest form factor possible.

Our BDCs are used extensively in military VSAT, SATCOM-on-the-move, emergency services, aeronautical, Earth observation and other applications. We use only the highest quality components and technology, so our BDCs can seamlessly meet the demands of high throughput satellites (HTS) and produce a consistently flat frequency response.

What is a BDC

What is a BDC?

A block downconverter is a small box mounted behind a satellite dish or in an outdoor hub. It translates a block of C, X, Ku or Ka-band input frequencies into L-band. Unlike a low noise block downconverter (LNB), which contains a low noise amplifier (LNA) in its housing, a BDC works with an external LNA to provide simultaneous reception of an entire band.

Why use a BDC

Why use a BDC?

Block downconverters (BDCs) are used when you want to cover an entire satellite band with a single antenna. You could potentially do this with multiple low noise block downconverters (LNBs), but you would need to use a waveguide splitter or switch – which would add to your noise figure and costs, and decrease your local oscillator (LO) stability.


How does a BDC work?

First, a high-quality LNA amplifies your satellite signal to a point where it can be split with minimal noise figure impact. Second, your split signal is fed into your BDCs, and then into your receivers. How many BDCs do you need? It depends on your bandwidth requirements. A pair of BDCs, for example, can cover 10.7 GHz to 12.75 GHz.


PLL vs. External Reference

There are two main types of BDCs: phase-lock loop (PLL) and external reference. The kind you need depends on your phase noise requirements – but generally, PLL is used for receiving only and external reference is used for 2-way satellite communication. If you need maximum data throughput or a low bit error rate (BER) – you need an external reference BDC.


Need a Custom BDC?

Orbital’s engineers can customize bandwidth, input and output connectors, DC input, dual power options and more. Most importantly, we can customize your signal gain to optimize compression point and noise distribution. We have a wealth of experience going back to the ‘70s – so if you have a custom need, we can meet it. Please don’t hesitate to ask.

Explore our range of block downconverters


C-band block downconverter (BDC)


Orbital Multi and Fixed LO BDC


Orbital Multi and Fixed LO BDC


X-band block downconverter (BDC)