COFDM, or Coded Orthogonal Frequency Division Multiplexing, is a modulation technique that provides high-quality transmission quality for terrestrial broadcast channels. It is designed to handle a high degree of multipath propagation, thus ensuring stable and reliable transmission.
This innovative approach has a wide range of applications, including Digital Video Broadcasting – Terrestrial (DVB-T) and WLAN. By converting blocks of modulated signal samples into the frequency domain using iFFT, COFDM ensures efficient use of bandwidth. Additionally, it inserts guard intervals into the spectrum to prevent inter-symbol interference.
One unique feature of COFDM is that each subcarrier is arranged in such a way that it does not interfere with other subcarriers, eliminating the need for filtering in the frequency domain. This helps solve the problem of frequency-selective fading. Forward error correction coding (FEC) is used for error correction purposes.
OFDM, or Orthogonal Frequency Division Multiplexing, is another interrelated technique. It divides high-speed modulation streams among closely spaced subcarriers, making it less sensitive to frequency-selective fading. Widely used for radio and telecommunications standards like Wi-Fi, WiMAX, LTE/LTE-A, and others, OFDM ensures fast data transmission with high spectral efficiency.
FAQs
What is COFDM used for?
COFDM is used for terrestrial broadcast channels, including Digital Video Broadcasting – Terrestrial (DVB-T) and WLAN. It is designed to handle a high degree of multipath propagation, making it ideal for stable and reliable transmission.
What is the difference between COFDM and OFDM?
COFDM and OFDM are interrelated techniques used for efficient data transmission. While COFDM is mainly used for terrestrial broadcast channels, OFDM is used for radio and telecommunications standards like Wi-Fi, WiMAX, LTE/LTE-A, and others. OFDM divides high-speed modulation streams among closely spaced subcarriers, making it less sensitive to frequency-selective fading.
In Summary
- COFDM is a modulation technique ideal for terrestrial broadcast channels, including DVB-T and WLAN.
- It is designed to handle multipath propagation, ensuring stable and reliable transmission.
- COFDM uses iFFT to convert blocks of modulated signal samples into the frequency domain and inserts guard intervals into the spectrum.
- OFDM is an interrelated technique used for radio and telecommunications standards like Wi-Fi, WiMAX, LTE/LTE-A, and others.
- OFDM divides high-speed modulation streams among closely spaced subcarriers, making it less sensitive to frequency-selective fading.
