In satellite communications systems, a narrow beam from a satellite station antenna that illuminates, with high irradiance, a limited area of the Earth by using beam (directive) antennas rather than Earth-coverage antennas.

The jamming of a specific channel or frequency. [JP 1-02]

In facsimile systems, optical scanning in which a scanning spot is moved across the object and the scanning spot size is determined by the illuminated area of the spot.

1. The size of the electron spot on the face of a cathode ray tube.
Note: The spot size is larger than the diameter of the electron beam because of the spillover of electrons into adjacent areas of the screen near the spot. The spot size is a function of the ability of the tube to focus the electron beam,… (Read More →)

In facsimile systems, the speed of the scanning or recording spot along the available line.
Note: The spot speed is usually measured on the object or on the recorded copy.

Supplemental Port Request

Supplemental Port Request 1 – Cancel

Supplemental Port Request 2 – Change Date

Supplemental Port Request 3 – Update Data

1. Telecommunications techniques in which a signal is transmitted in a bandwidth considerably greater than the frequency content of the original information.
Note: Frequency hopping, direct sequence spreading, time scrambling, and combinations of these techniques are forms of spread spectrum. [INFOSEC-99]
2. A signal structuring technique that employs direct sequence, frequency hopping or a hybrid of these, which can be… (Read More →)