The glideslope works in the same general fashion as the localizer and uses the same encoding, but is normally broadcast to produce a centerline at an angle of 3 degrees above horizontal[lower-alpha 1] from an antenna beside the runway instead of the end. The only difference between the signals is that the localizer is broadcast using lower carrier frequencies, using 40 selected channels between 108.10 MHz and 111.95 MHz, whereas the glideslope has a corresponding set of 40 channels between 328.6 and 335.4 MHz. The higher frequencies generally result in the glideslope broadcast antennas being smaller.