8.5.8 Advantages And Disadvantages Of CDMA

CDMA offers several advantages that distinguish it from frequency- and time-division systems. Because all users share the same bandwidth simultaneously, frequency planning is simplified and spectrum can be utilized flexibly. The soft capacity characteristic allows the system to accommodate temporary overload conditions with gradual performance degradation rather than abrupt blocking. Wideband spreading can also provide resilience to narrowband interference and multipath effects.

However, CDMA introduces significant challenges. System performance is highly sensitive to power imbalance, making fast and accurate power control essential. Capacity is interference-limited and depends on aggregate user load rather than discrete channel allocation. Synchronization and code acquisition are more complex than in FDMA or TDMA, particularly in asynchronous environments. Furthermore, increasing processing gain to improve interference tolerance requires additional bandwidth, which may not always be available.

Thus, while FDMA is often constrained by amplifier linearity and TDMA by timing precision, CDMA is primarily constrained by interference management and power control stability.