Ask your doctor for a vitamin D test. Be specific and ask for a 25(OH)D test. There is another type of blood test for vitamin D, called a 1,25(OH)âD test, but the 25(OH)D test is the only one that will tell you whether youâre getting enough vitamin D. Order an in-home test. These tests are sent to your home.
Carrier signal: A frequency in a communications channel modulated to carry analog or digital signal information. For example, an FM radio transmitter modulates the frequency of a carrier signal and the receiver processes the carrier signal to extract the analog information. An AM radio transmitter modulates the amplitude of a carrier signal.
Carrier signal can be defined as a high frequency signal that is modulated by the modulating or the information signal. This carrier signal increases the range and distance the information signal can travel. Along with the distance carrier signal also improves the signal quality. To understand this we can consider a carrier signal as some bus, train, an aeroplane or any transport vehicle i.e. a carrier of some sort and the information signal as the passengers of the carrier. See it this way, a person can walk comfortably for a few kilometers.