What is 64QAM?

64QAM, quadrature amplitude modulation, means quadrature amplitude modulation.

64 QAM (quadrature amplitude modulation) is a digital frequency modulation technology, which is usually used to send downlink data in the network using coaxial cable. 64QAM In a 6MHz channel, the transmission rate of 64QAM is very high, which can support the peak transmission rate of 38.0 15Mbps at the highest.

However, it is very sensitive to interference signals and difficult to adapt to noisy uplink transmission (from cable users to the Internet). See QPSK, DQPSK, CDMA, S-CDMA, BPSK and VSB.

Extended data:

It has the characteristics of high modulation efficiency, high signal-to-noise ratio of transmission channel and high bandwidth utilization rate, and is suitable for cable TV cable transmission. The DVB-C modulation widely used in China's cable TV network is QAM modulation.

QAM is a technique combining amplitude and phase modulation. It uses both amplitude and phase of carrier to transmit information bits, and different amplitude and phase represent different coded symbols. Therefore, in the case of the same minimum distance, more constellation points can be accommodated in the QAM constellation diagram to achieve higher frequency band utilization.