Cable Modems Explained: OFDM vs OFDMA
Learn > Cable Modem & Routers > Cable Modems Explained: OFDM vs OFDMA

A cable modem uses a coaxial cable to bring an Internet connection into your home. The job of a cable modem is to directly communicate with your Internet service provider (ISP) to make this happen. Because a cable modem uses a wired connection, it offers a reliable connection. When you pair your cable modem with a router (or use a cable modem router) you can get Wi-Fi in your home.

In previous articles we have discussed the must-haves when selecting a cable modem.

We’ve also explained the benefits of upstream and downstream channels and the difference between fixed and switchable frequencies.

In this article, we are exploring what OFDM and ODFMA means and the difference between them.


What is OFDM?

OFDM stands for orthogonal frequency division multiplexing. It is a form of multi-carrier modulation. What this means is that a cable modem that supports OFDM send and receive voice and data signals at the same time without having to be filtered.

Traditionally, data is sent over a radio frequency (RF) signal bit by bit over a single channel. This method is highly vulnerable to interference. OFDM avoids interference and makes it easier to receive data accurately while maintaining the same throughput by transmitting data parallelly across multiple carriers (or channels) within the OFDM signal. For example, Wi-Fi 5 used 52 data-carrying sub-carriers, while Wi-Fi 6 uses 234. These numerous split signals keep the same data rate as if it was the original signal even though it is split.

The key takeaway is the OFDM makes efficient use of the available spectrum by using multiple carriers for data signals and reduces interference. OFDM is a common technology used in high data rate wireless systems because it is so advantageous. But OFDMA is even better.


What is OFDMA and how is it different than OFDM?

OFDMA stands for orthogonal frequency division multiplexing access. It is an extension of OFDM. The difference is that OFDMA is multi-user where OFDM is single-user. It has 3x higher throughput than single-user OFDM for short packets of data or multiple endpoints. OFDMA combines transmissions and sends frames to multiple endpoints simultaneously. It is more efficient with lower latency transmission. This makes OFDMA ideal for things like IoT devices, video, online gaming, and automation applications.

Whether you choose a cable modem that supports OFDM or OFDMA, ​Hitron’s cable modems and cable modem routers are designed to improve your home Wi-Fi. ​Ask your ISP about Hitron’s DOCSIS 3.0 and 3.1, Wi-Fi 6 ready cable modems and cable modem routers today.

For more information on networking solutions check out Hitron’s ​Learn Page​.

Learn More about Cable Modems & Routers

Cable Modems Explained: Channel Bonding

Too much device traffic on one home Wi-Fi network leads to congestion which leads to slow Internet. That’s why modern cable modems have evolved to create more than one “lane” – or channel – to let that traffic through. This feature is called channel bonding. If you...

Choosing the Right Cable Modem or Cable Modem Router

So, you decided to buy a cable modem or cable modem router for your home network. Now you need to figure out which is best for you. Choosing the right device depends on your specific home setup and your overall Internet needs. Here are some things to consider when...

Cable Modems Explained: Wi-Fi 6 vs 802.11ac

The first version of Wi-Fi was called 802.11. As new generations came out, the name was represented as 802.11 followed by a combination of letters. For example, 802.11b, 802.11g and 802.11n. The difference between these standards is the bandwidth speed, frequency...

Cable Modems Explained: Compatibility with Service Providers

A modem is a device that connects your computer or device to the Internet. A cable modem gives you a cable Internet connection. On its own, a cable modem provides a wired connection. To get wireless Internet (Wi-Fi) you need a router or cable modem router. However,...

Are All Cable Modem Router Combos the Same?

While upgrading networking equipment can be a hassle, it’s an essential part of optimizing your Wi-Fi and getting the best speeds and connection possible. Before you make a purchasing decision, it’s important to understand how cable modems, routers, and cable modem...

Related Articles