Orthogonal Frequency Division Multiplexing & Measurement of its Performance
نویسنده
چکیده
OFDM is defined as a form of multi-carrier modulation where the carrier spacing is carefully selected so that each sub carrier is orthogonal to the other sub carriers. As the sub carriers are orthogonal, the spectrum of each carrier has a null at the center frequency of each of the other carriers in the system. Orthogonal Frequency Division Multiplexing (OFDM) is a promising technique to perform multicarrier modulation with maximum utilization of bandwidth and high performance characteristics profile against fading in multipath communication. OFDM has become very popular since its inception. This is used in many communication systems. OFDM is one of the dominant techniques of present day wireless communication and also for future usage in mobile industries. The key requirements for future mobile communications include much higher peak data rate, spectrum efficiency, and user capacity in high mobility environments. OFDM is a kind of Multi Carrier Transmission system where a single data stream is transmitted over a number of subcarriers. OFDM can be used to convert frequency-selective channel into a set of parallel frequency-flat sub channels. Keywords— Multiplexing, performance, bit error rate, orthogonality.
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