Analog Voice Characteristics. Analog is defined as a signal that has a continuously and smoothly varying amplitude or frequency. Human speech, and everything else you hear, is in analog form, and early telephone systems were analog as well. Analog signals are often depicted as smooth sine waves, but voice and other signals are more complex than that, since they contain many frequencies.
Key Points. 1  Fatigue in cancer patients may have more than one cause. 2  How cancer treatments cause fatigue is not known. 3  Anemia is a common cause of fatigue. 4  Side effects related to nutrition may cause or increase fatigue. 5  Anxiety and depression are the most common psychological causes of fatigue in cancer patients. The emotional stress of cancer can cause physical problems, including fatigue. It's common for cancer patients to have changes in moods and attitudes. Patients may feel anxiety and fear before and after a cancer diagnosis. These feelings may cause fatigue.
Anemia can be caused by iron deficiency, vitamin deficiency, chronic disease, bone marrow disease, autoimmune disorders and sickle cell anemia, among other causes. Anemia can be temporary or chronic, and its severity ranges from mild to marked. Cancer can cause extreme fatigue and weakness.