Define gain and loss in antenna terminology and how they contribute to link budgets.

• A. Gain adds to the signal in a preferred direction; loss reduces signal via feedline, connectors, and environment; net budget uses gains minus losses
• B. Gain measures antenna weight; loss measures coax weight
• C. Gain adds to the signal in a random direction; loss reduces signal via energy absorption
• D. Gain is the same as power supply; loss refers to battery drain

Answer: (A)

Gain is how effectively an antenna concentrates energy in a chosen direction, boosting the signal toward the target compared with an isotropic radiator. Losses are anything that weaken the signal as it travels—from the feedline and connectors (cable and connector losses) to environmental and atmospheric effects (rain, foliage, multipath, impedance mismatches). When you build a link budget, you add the transmitter and receiver antenna gains and subtract the total losses along the path to determine the net received signal or the link margin. This is why the correct description emphasizes gains adding to the signal in a preferred direction, losses reducing it through the feedline, connectors, and environment, and the overall budget being gains minus losses. In practice, these quantities are expressed in decibels (dB), with antenna gain given in dBi and losses in dB.