Difference between TDMA and CDMA (With Table)

Because the amount of possible routes is relatively restricted, industry executives and engineers have predicted the eventual congestion of concurrent calls since the creation and marketing of cellular networks. RF industry experts are increasingly employing techniques to address these issues. TDMA and CDMA are two examples of such techniques.

The multiple access technique is chosen during the design and standardization of cellular networks. So, to understand the two techniques, this article is here to help out with the differences and features between TDMA and CDMA using important pointers to remember and a descriptive table.

TDMA vs CDMA

The difference between TDMA and CDMA is that TDMA stands for “Time Division Multiple-Access” which means this technique has the ability to trim down the timeline into several smaller channels whereas CDMA stands for “Code Division Multiple-Access” which implies that this technique allows multiplexing into a single channel. Both the techniques are widely used in the calling and network management industries.

TDMA is an abbreviation for Time Division Multiple Access. Instead of splitting the principal RF bandwidth into two or more inter-channels, TDMA divides it into two-time frames. Each slot has the same RF spectrum as the others, yet they are capable of holding independent conversations. If the primary channel is split into four-time frames, for example, each one will take a fourth of the initial time to send the data and content.

CDMA does not divide the entire RF bandwidth into successive time slots or inter-channel but instead provides each one a special identifier. Unlike the TDMA technique, CDMA transmits at the same frequencies in every position. In addition, unlike TDMA, CDMA transmits single slots at the same time. CDMA combines the advantages of both methods (TDMA and FDMA), allowing several users to share the same frequency range while being differentiated by a code.

Comparison Table between TDMA and CDMA

Parameters of ComparisonTDMACDMA
Full FormTime Division Multiple AccessCode Division Multiple-Access
Sync and Code RequirementCrucial synchronization and no code word is required.Sync is not required and code words are required. 
CostOverall cost is lower than CDMA.Plantation cost is very high but maintenance monthly cost is pretty less.
Flexibility and EfficiencyMedium flexibility in operation and execution.Highly flexible and very much efficient when compared to TDMA.
Mode of OperationThe timing of broadcast through satellite is the only thing that TDMA shares, not the stream.By giving a distinct code to each slot, the CDMA distributes both network bandwidth among multiple stations.

What is TDMA?

The term TDMA is an acronym for “Time-Division Multiple Access.” In this technique, the channel is chopped or divided into successive temporal parts using TDMA sub-channels. Users of the route will take turns reading and sending data in a round-robin fashion.

When you break this down, the channel is only used by a single person at any particular time. Each user only utilizes the channel for brief periods of time at a time, and his or her right to use resources is temporarily revoked to allow individuals to use the stream.

Actually, TDMA has remained a part of GSM for a long period of time, despite the fact that it is an outdated technology that is rapidly becoming outdated. FDMA was more common in conventional systems and was utilized in 2G networks before being superseded by TDMA innovation. The connection of a user going through one cell to another is dropped and the user is instantly accessed through the internet to which he or she is migrating in TDMA.

FDMA was more common in conventional systems and was utilized in 2G networks before being superseded by TDMA innovation. The connection of a user going through one cell to another is dropped and the user is instantly accessed through the internet to which he or she is migrating in TDMA.

What is CDMA?

CDMA is an acronym for Code Division Multiple-Access. It’s also a type of combining in which many signals can share a single communication path. With exception of TDMA, CDMA allows several users to share the very same channel simultaneously at the same timespan.

As a result, several users are concurrently sending and receiving data. Multicast, a form of modification that takes each user’s flow of binary digits and distributes them out throughout the stream in a pseudo-random way, is the only way to do this. The recipient simply analyses the jumbled bits, or, to put it another way, un-randomizes them to make them intelligible.

The principal RF channel is divided into four coded slots using CDMA. Each slot may hold a different discussion. Because the receivers can only reassemble data sets from an emitter with the same coding, this is the case. However, there is a problem with this technique.

Although the receiver receives and decodes signals with various implementations and frequencies, they begin to resurface as noise. This implies that as the overall user base grows, so does the noise exposure on any specific system. As a result, it has an impact on total coverage.

Main Differences Between TDMA and CDMA

  1. TDMA stands for Time Division Multiple Access whereas CDMA stands for Code Division Multiple-Access.
  2. TDMA is compatible with GSM 2G technology whereas CDMA is compatible with some modules of WCDMA 3G networks.
  3. TDMA allows a single user to use the channel whereas CDMA can handle multiple users at the same time in one channel.
  4. TDMA setup and maintenance costs are lower than CDMA maintenance and setup cost.
  5. No codeword is required in TDMA whereas codeword is necessary for the CDMA technique.

Conclusion

CDMA’s feasibility is significantly higher than TDMA’s. CDMA seems to be more reliable, resilient, and covers a larger region; but, when it concerns the device’s battery capacity, TDMA gives a longer battery life since it does not send data continually, whereas CDMA does.

Both of them have abbreviated meanings that shed insight on the method in which they optimize channels. Performance reviews using CDMA and TDMA show that the deterioration might be inverse of the third or fourth degree, making the appropriate selection of a desirable receiver limit much more critical than with traditional FM two-way radio models.

References

  1. https://www.pcmag.com/encyclopedia/term/cdma
  2. https://www.sciencedirect.com/topics/engineering/time-division-multiple-access
x
2D vs 3D