FDM vs. FDMA. Frequency Division Multiplexing, or FDM, is a multiplexing technique for the physical layer that allows multiple low bandwidth signals to share the same high bandwidth frequency range.It is achieved by allocating a smaller frequency range to each signal that is using the same channel.ummary: 1. FDM is a physical layer multiplexing technique, while FDMA is a data link layer access method. 2. Using FDM to allow multiple users to utilize the same bandwidth is called FDMA.
Checking your iron levels is one of the most important tests that everyone should have done on a regular basis as part of a preventive, proactive health screen; it can be done with a simple blood test called a serum ferritin test; your ferritin level should be between 20 and 80 ng/ml, and 40 to 60 is ideal.
The iron test is used to measure the amount of iron that is carried by transferrin, a protein that transports iron from the intestine to cells that use iron. The amount of iron within the blood varies throughout the day, and from one day to the next. An iron blood (serum) test is therefore not a useful measure of iron status if it is used on its own. Serum iron is therefore often requested in combination with other tests of iron status.