Spread spectrum. In telecommunication and radio communication, spread-spectrum techniques are methods by which a signal (e.g., an electrical, electromagnetic, or acoustic signal) generated with a particular bandwidth is deliberately spread in the frequency domain, resulting in a signal with a wider bandwidth.
Lipids are one of the four major groups of organic molecules; the other three being proteins, nucleic acids (DNA), and carbohydrates (sugars). Lipids are made up of the same elements as carbohydrates: carbon, hydrogen, and oxygen.
In biochemistry, lipids are molecular organic compounds, composed largely of carbon and hydrogen, that are essential for cell growth. Lipids are non-soluble in water and combine with carbohydrates and proteins to form the majority of all plant and animal cells. They are more commonly synonymous with the word fats when speaking in terms of personal health. Although all fats are lipids, not all lipids are fats.