Fixed Channel Allocation (FCA)
Fixed Channel Allocation (FCA), is a strategy of fixed channels or voice channels allocations to be allocated to cells. Once channels are allocated, they are not changed. This type of allocation is used to maximize frequency usage. If a user makes a call and cell is occupied then call is blocked. Borrowing channels from other cell solves this problem.
Dynamic Channel Allocations (DCA)
Dynamic Channel Allocations (DCA), is a strategy of allocation of channels or voice channels on request basis. Whenever a user makes a call requst then Base Station makes a request to Mobile Station Center to allocate the channel. Allcation increases when traffic increases.
Following are the important difference between FCA and DCA.
| Sr. No. | Key | Fixed Channel Allocation (FCA) | Dynamic Channel Allocations (DCA) |
|---|---|---|---|
| 1 | Channel Allocation | Fixed number of channels or voice channels are alloted. | Channels to be alloted are not fixed initially. |
| 2 | Blockage | If all channels are occupied, then user call is blocked. | If all channels are blocked, then Base Station(BS) requests more channels from Mobile Station Center(MSC). |
| 3 | Frequence Usage | Frequency usage is very high being cell channels are seperated using minimum reuse distance. | Frequency reuse is not maximum because of random channel allocation. |
| 4 | Tangible | A hardware can be touched being a physical electronic device. | Softwares being digital can be seen but cannot be touched. |
| 5 | Algorithm | No need to complex algorithm. | Algorithm to determine efficient channel availability is quite complex in DCA. |
| 6 | Cost | FCA is cheaper than DCA. | DCA is costly as real time computation needed. |
| 7 | Cell Allocation | Once call is complete, channel remains with the cell. | Once call is complete, channel is returned back to Mobile Station Center. |
| 8 | MSC | Mobile Station Center has less burden. | Mobile Station Center has high signal load, and has more responsibilites. |