MMDS technology is also a wireless communication technology. The full name of this technology is Multichannel Microwave Distribution System. The Chinese meaning is wireless multi-channel microwave distribution system. MMDS now uses traditional modulation techniques, but future technologies will be based on VOFDM (Vector Orthogonal Frequency Division Multiplexing), where the receiver combines with the reflected signal to generate a stronger signal. This technology is inexpensive and is often used in small business access networks that are remote from service centers. It is sometimes referred to as WDSL or as broadband wireless technology. The most notable feature of MMDS is that the local oscillator points of each frequency reducer can be different. The user can select the frequency point, that is, the multi-point local oscillator. Therefore, the signals after frequency conversion of each frequency reducer can fall on the VHFI and III of the TV standard channel respectively. Bands; supplemented A and B bands; UHF's 13~45CH (band), which is of great benefit to users avoiding the channels of local open wireless TV or CATV. The early MMDS was mainly a one-way unassigned image service transmission system. It is now possible to send and receive data signals at a faster rate than T-1. MMDS does not need to deal with local telephone and cable telecommunications companies too much. These companies are generally reluctant to cooperate and do not want to open their own networks. In an MMDS system, it is usually connected to a wireless modem using Ethernet.