Modulation is the process of impressing an information bearing signal to a carrier for effective transmission over a long distance. example Am and FM used in radio transmission Analogue baseband signals of 0-4000Hz are shifted to 60-64Khz range. Communication systems often do not carry signals in baseband (with the exception of local loop) Wavelength of a radio wave in free space is the speed of light/the frequency. That means a 4KHz voice signal has a wave length of 75000m (300000/4). We cant possibly make an antenna to receive such signals Why an antenna cannot receive analogue baseband signal of 0-4000Hz? I heard we need a very large antenna to receive analogue baseband signal of 0-4000Hz? why?