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 ferritin test is often ordered as part of a panel of tests that examine the levels of body iron and the effects of abnormalities in iron storage.It may be ordered together with an iron level, a total iron binding capacity test, or blood cell counts. Medically Reviewed by a Doctor on 8/12/2015. ferritin test is a laboratory blood test that measures the amount of ferritin in a person's blood stream. Ferritin is the major iron storage protein in the body, so the ferritin test is ordered as an indirect way to measure the iron stores in the body.