1. Additional improvements were introduced via the Quadrature Amplitude Modulation ( QAM ) encoding system. 2. Mathematically both of these are considered a special case of quadrature amplitude modulation ( QAM ). 3. "' QAM "'is a digital television standard using quadrature amplitude modulation . 4. And this is without going into the complexities of Orthogonal frequency-division multiplexing and Quadrature amplitude modulation . 5. Some satellites transmit several BPSK streams at the same frequency in quadrature, in a form of quadrature amplitude modulation . 6. The modulation technique of the color subcarrier is quadrature amplitude modulation ( QUAM ) both in PAL and NTSC systems. 7. In the NTSC and PAL color systems, U and V are transmitted by using quadrature amplitude modulation of a subcarrier. 8. The modulation method in DVB-T is COFDM with either 64 or 16-state Quadrature Amplitude Modulation ( QAM ). 9. The 12 and 18 Mbit / s modes use OFDM with QPSK . The fastest four modes use OFDM with forms of quadrature amplitude modulation . 10. The maximum data rate assumes use of the optional 160 MHz channel in the 5 GHz band and 256 QAM ( quadrature amplitude modulation ).
