Watching an OFDM video tutorial is undoubtedly the best way to learn about OFDM basic facts, and get a grasp of the subject. However, in the interim, this short article will teach you some information about basic OFDM and how it is used. OFDM stands for Orthogonal Frequency-Division Multiplexing, and it is a broadband multicarrier modulation method that provides a far better solution for the high-speed data transfer that is frequently required today.
The speed at which data is transmitted will have an effect of the likelihood there may be problems with the transmission. The higher the speed, the more likely there will be line noise and interference, and the data may become corrupted. There will usually be much less interference when data is sent at a slow rate. A multicarrier modulation method, as used by OFDM, allows for many small pieces of data to be sent and then later combined to arrive as a single unit.
In the instance of OFDM, transmitted data is broken into up to 52 subcarrier streams and after multiplexed into one data stream. This method allows data to be sent at a slower rate, but in a very fast time frame.
Surprisingly, the concept of OFDM is far from recent - in fact the possibility of achieving data transfer this way has be a concept since the 50s, and more widely researched in the 60s. The method was originally referred to as multicarrier modulation, but needless to say, the technique would have been extremely hard if not impossible to implement as the hardware for such technology was simply not available at the time. The computer technology we have today finally makes this type of data transfer possible.
The increase in interest for OFDM is due to the demand for higher speed data transmissions during recent years. OFDM it is the best solution for fast data transfer we have up to now, because it delivers data extremely quickly without data errors that were previously apparent in multipath broadcasting. The main advantage of using OFDM is the increase in bandwidth efficiency it creates. This means it is possible to send large amounts of data without interference and noise. Bandwidth efficiency is measured at bits per second per Hertz, which is written as bps/Hz.
Wireless high-frequency data transfer usually has multipath issues, but these are eliminated with OFDM. In theory, short-wavelength signals should be easily received over short distances, as long as the receiving and transmitting antennas are within line of sight. However, in reality buildings, hills, trees and even people, effect the transmission by reflecting parts of the signal. Unfortunately, this means a copy of the original signal is also sent and received by the antenna. This often results in data cancellations and other issues. OFDM divides the data into small pieces, and transmits it at low rates. This results in far fewer anomalies and the data arrives faster.