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.
1 Organic compounds are those that contain carbon (e.g. carbohydrates, lipids, proteins, nucleic acids). 2  For example, a piece of human liver contains 80% water, 12% protein, 5% fats, 2% nucleic acids, 1% carbohydrate and less than 1% of other substances. 3  Many organic molecules are assembled from small repeated units. Proteins are macromolecules made from amino acids, nucleic acids are made from nucleotides, carbohydrates are made from monosaccharides or simple sugars, and lipids are made from fatty acids and glycerol.