CDMA Frequency Allocation - CDMA

What is CDMA - Frequency Allocation?

Major advantage of CDMA comes in using the same allocated frequency in each and every sector of cell.

In IS-136 and analog cellular systems, CDMA has a repeat factor of seven cells, including three sectors each. It can be observed that only one out of every 21 channels is available to each sector. CDMA is specially designed for sharing the same frequency in each sector of each cell. For all those users, who use cdma2000 coding rather than IS-95, the system is more efficient.

• To not interfere with neighbor cells, a radio resource is allocated in FDMA or TDMA -
• Same frequency band (or timeslot) is not used with neighbor cells.

In the diagram, the left side shows the cell allocation having seven frequency bands.

In real time, due to complexity in radio propagation and uneven allocation of cell, it’s not easy to allocate frequency.

Biggest advantage of CDMA technology is that it shares the same frequency and arrangement of the frequency is not treated as an issue.

As the frequency is used simultaneously among all channels, all cells use an identical radio resource.

• In CDMA, frequency allocation is not compulsory.
• CDMA cellular system is easy to design because of this.