Difference between CDMA and OFDM

OFDM is a multi-carrier transmission technology. Orthogonal frequency division multiple access (OFDM) is used to obtain a higher data rate in the multipath fading environment of mobile communication. carrier division multiple access (CDMA)  is a digital cellular network standard and it can utilize speed spectrum technology. This technology, the user may transmit at the same time using the same frequency band but it can be using different codes so that we can decode to identify a particular user. Here this post gives information about the difference between OFDM and CDMA are given below.  

The main key difference between OFDM and CDMA are given below:

  • While we have to use OFDM transmission bandwidth is maximum up to system bandwidth while using CDMA is equal to full system bandwidth.
  • OFDM is very long and it depends on subscriber spacing and it is independent of the system bandwidth.while in CDMA is very short and it is inverse of the system bandwidth.
  • OFDM is free from multipath up to the length of cyclic prefix but CDMA is very difficult bone 5 MHz.
  • OFDM is a separation for frequency and time, scrambling and spreading can also be used while in CDMA is scrambling and orthogonal spreading codes.
  • OFDM is vulnerable to narrowband distortion and interference while CDMA is averaged across channels due to spreading.
  • Equalization in OFDM is easy for all bandwidth because of frequency domain representation but in CDMA is is very difficult above 5MHz.
  • OFDM is possible and needs very accurate real-time feedback of channel conditions from receiver to the transmitter while in CDMA frequency selective scheduling which is no possible.

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