- The different types of multiplexing used in wireless communications are constantly evolving, with each generation of technology introducing new advancements.
- 3G, 4G, and 5G all use different types of multiplexing, with 4G and 5G utilizing Orthogonal Frequency Division Multiplexing (OFDM) and 3G using Code-Division Multiple Access (CDMA).
- OFDM allows for high-speed data transmission with minimal loss, while CDMA is reliable for voice calls, texting, and lower-speed data access.
- OFDM is the future-proof method of multiplexing, with plans for it to be used in the upcoming 6G network.
- OFDM is the most widely used and reliable method of multiplexing in wireless communications.
The different types of multiplexing in wireless communications are in a constant state of flux. You can look at the differences between 3G, 4G, and 5G just to get an idea. Beyond the differences in speed and transmission strength, there are advances in technology that separate the types of multiplexing.
Wireless communications are here to stay, and multiplexing has been a part of networking since the invention of computer networks. With this in mind, which different types of multiplexing do 3G, 4G, and 5G use?
This is a complex answer, especially given the stark differences in network technology with each generational leap. However, if you’re new to the world of communications or networks, it is certainly an interesting topic.
This guide will attempt to discuss the different types of multiplexing used by these technologies, how they are used, and what makes them viable for the method of transmission.
3 Different Types of Multiplexing in Communications: Side-by-Side Comparison
|Orthogonal Frequency Division Multiplexing
|Orthogonal Frequency Division Multiplexing
|Code-Division Multiple Access
|Wireless Standard Used
|5G New Radio
|4G Long Term Evolution
|3G on specific networks
|Date of Introduction
|Method of Transmission
|Multi-carried modulation through subcarriers that orthogonally spaced
|Multi-carried modulation through multiple orthogonally spaced subcarriers
|Spread spectrum multiplexing for data, text, and voice calls
|Latest Generation of Wireless Standard
|Still in Use?
|Yes, but is being phased out by most major carriers
3 Different Types of Multiplexing in Communications: What’s the Difference?
All three of the different types of multiplexing have the same overall goal. A network is only worth using if it can readily share the bandwidth with other devices, after all. As such, you’ll likely not some very prominent similarities between all three.
4G and 5G both use OFDM or orthogonal frequency division multiplexing. The only real difference is the type of OFDM for 5G has been updated to allow for the higher bandwidth and data rates of 5G.
Method of Transmission
Both 4G LTE and 5G NR use OFDM, a rather sophisticated implementation of multiplexing. The actual method by which data transmits is quite complex. OFDM splits the transmission into multiple bands, which are orthogonally located next to one another.
In mathematics, something being orthogonal means it is positioned in a right angle or 90 degrees. In data, orthogonal transmission would relate to the data stream being independent but also affecting a particular variable, asset, or other piece of information.
Having the data stream split in such a manner allows for it to prevent data from spreading, which could lead to lost transmissions. The actual mathematics behind OFDM are quite complex, but it is the latest standard. It was introduced with the first version of the 4G network standard and is the method of choice for 5G.
3G uses CDMA, or Code-Division Multiple Access. CDMA itself dates back to the early days of commercially available mobile phone coverage. The multiplexing in use by CDMA allows for it to share one data stream across multiple mobile phones.
CDMA used to be carrier-specific, meaning other phone networks might utilize an older standard like GSM. CDMA is slightly more sophisticated than GSM but doesn’t really fit the needs of modern cell networks.
What Makes it Viable
OFDM allows for 4G and 5G networks to reliably transmit high-speed data to a device with minimal transmission loss. Inevitably, with wireless communications at least, there is going to be signal loss.
This can be due to the distance from the base station or the structure of the data stream in the face of other interference.
OFDM has integrated spread reduction, meaning the data stream is able to stay stronger for further distances. When you also consider the millions of mobile devices in the world, OFDM allows for network connectivity with minimal congestion.
It is a complicated method of multiplexing, but it has allowed for connectivity that was once thought impossible during the early days of mobile networks.
CDMA was a reliable means of handling voice calls, texting, and mobile internet access. The way it divides its data stream is a novel approach, handling things as a single massive band going to multiple devices.
This does result in users needing reliable access to nearby cell towers, as many early adopters of mobile internet might remember. Coverage is generally stellar but can be prone to congestion since you have multiple users sharing the same overall bandwidth.
Standards Established for Multiplexing
Now, all methods of multiplexing have their roots in older mathematical concepts. OFDM for example was first implemented in the 1960s but didn’t see widespread adoption until the late 2000s.
OFDM is the standard going forward, with revisions due as 6G looms on the horizon. It was established as an IEEE standard, 802.16, in 2001.
This is vital for the adoption of OFDM as a multiplexing standard, because all carriers have an established and understood standard they can use when designing networks.
CDMA lacks IEEE adoption but served as a standard method of multiplexing for years before the introduction of 4G networks. Early mobile phone users might remember the debates between CDMA and GSM.
CDMA provided more reliable access and still sees use as a means of lower-speed data access across the world. It has been the de facto standard for wireless communications for decades when looking past the United States and Europe.
How Futureproof Is It?
CDMA is not long for this world. As mobile phone carrier networks start pivoting towards widespread deployment of 5G networks, there isn’t much use for an older standard. CDMA will likely go the way of TDMA, another deprecated wireless standard.
Some carriers, like Verizon, may still keep on at least some CDMA components. As 5G NR becomes more viable, it is more likely users will be using OFDM on a daily basis, however.
OFDM allows for a lot more signal strength to be carried across devices, while also having blazing fast speeds. While there is always a bit of sadness that comes when a viable technology gets deprecated, CDMA has served its purposes for years now.
OFDM is future-proof, for the time being at least. While much isn’t known about the deployment of 6G, which is due for 2030 at the latest, it is known that OFDM will be the primary method of multiplexing used going forward.
3 Different Types of Multiplexing: Must-Know Facts
- Both 4G and 5G networks use OFDM.
- OFDM splits the signal into multiple streams that are closely spaced.
- OFDM allows for reliable data transmission of all aspects of mobile phone coverage.
- CDMA is an older standard, finding its roots in 1995 from Qualcomm originally.
- CDMA is still in use but in a limited deployment capacity.
- CDMA is more widespread, due to the lower costs associated with the networks in use.
3 Different Types of Multiplexing: Which One is the Best? Which One Should You Choose?
If you’ve got a newer cell phone, you’re using OFDM. There are rare instances when roaming where you might have to use 3G data access. By and large, however, you’re going to be using OFDM to transmit your social media feed, voice calls, and everything else you might use.
There really isn’t a lot of debate when it comes down to wireless multiplexing standards. You’ll want to use the most reliable and recent system on a network. As such, OFDM is the clear winner of any debate. It allows for reliable streams without compromising signal strength in coverage areas.
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