Access system and method for transmitting Ethernet signal and mobile communication signal

An access system for transmitting Ethernet signals and mobile communication signals, the access system comprising:

• a near-end host unit and N remote-end user units, wherein the near-end host unit is connected with an optical network unit for receiving and uploading the Ethernet signals, the near-end host unit being further connected with a base station for receiving and uploading the mobile communication signals, the near-end host unit is connected with the remote-end user units through category 5 cables or category 5 enhanced cables for transmitting the Ethernet signals and the mobile communication signals,
• wherein, the near-end host unit comprises:
• a host frequency conversion unit;
• a host central control unit;
• a downlink signal allocation unit;
• an uplink signal allocation unit;
• N uplink differential-to-single ended units;
• N downlink single ended-to-differential units;
• and
• N network transformer units,
• wherein after the downlink mobile communication signals from the base station enter the near-end host unit, the host frequency conversion unit performs down frequency conversion on the downlink mobile communication signals and sends to the downlink signal allocation unit;
• the host frequency conversion unit simultaneously outputs the internal clock reference signals thereof to the downlink signal allocation unit;
• the downlink signal allocation unit combines the frequency-converted downlink mobile communication signals and the clock reference signals via a combiner, and further allocates the signals to allocate the downlink into N paths of signals;
• the N downlink single ended-to-differential units perform the conversion from the singled ended signal to the differential signal on the N paths of signals, so as to match with the impedance of the category 5 cables or category 5 enhanced cables;
• after the signals are converted to the differential signals, the central control unit sends a pair of control signals respectively into uplink and downlink of each pair of the differential signals for conversion, and then loads the differential signals to the pair 4-5 of twisted pairs of the category 5 cables for transmitting;
• the uplink mobile communication signals from the user terminal are sent into the near-end host unit in the form of differential signals through the pair 7-8 of twisted pairs;
• in the near-end host unit, N uplink differential-to-single ended units convert the uplink mobile communication signals into the singled ended signals respectively to provide to the uplink signal allocation unit;
• the uplink signal allocation unit combines the N paths of signals into the intermediate-frequency uplink mobile communication signals, and finally the host frequency conversion unit converts the uplink mobile communication signals from the intermediate-frequency signals back to the radio-frequency signals to transmit to the base station;
• after the downlink Ethernet signals from the optical network unit are sent into the host unit, they are loaded to the pair 1-2 of twisted pairs of the category 5 cables or the category 5 enhanced cables via the corresponding network transformer units;
• the uplink Ethernet signals from the client side are transmitted from the pair 3-6 of twisted pairs of the category 5 cables or the category 5 enhanced cables to the optical network unit via the corresponding network transformer units;
• the remote-end user unit comprises a terminal frequency conversion unit, a user side central control unit, N single ended-to-differential units, N differential-to-single ended units, an Ethernet data processing unit, and N network transformer units;
• the Ethernet signals and the mobile communication signals transmitted from the near-end host unit enter the remote-end user terminal via EMI port;
• two pairs 1-2 and 3-6 of twisted pairs are connected with the corresponding network transformers;
• each network transformer is connected with the Ethernet data processing unit which provides the broadband access service;
• the central control unit extracts the control signals from the pair 4-5 of twisted pairs, and resolves the control information transmitted from the near-end host unit so as to control the terminal frequency conversion unit and the Ethernet data processing unit, and upload the working statuses thereof to the central control unit of the host unit at regular time;
• the differential-to-single ended unit finishes the differential-to-single ended conversion, and separates the downlink mobile communication signals and the clock reference signals from the pair 4-5 of twisted pairs via high and low pass filter, and then sends the separated downlink mobile communication signals to the remote-end frequency conversion unit for performing downlink transmission, and sends the separated clock reference signals to the remote-end frequency conversion unit for providing reference for the phase locked loop circuit;
• the uplink mobile communication signals are converted to the intermediate-frequency signals via the remote-end frequency conversion unit, and loaded to the pair 7-8 of twisted pairs through the impedance change of the single ended-to-differential units and the single ended-to-differential conversion in order to transmit to the near-end host unit,
• wherein the near-end host unit further comprises a host side power supply unit for outputting the direct current of +48 v, which is fed into the two pairs 1-2, 3-6 of twisted pairs through the secondary coil of each network transformer unit, wherein the pair 1-2 of twisted pairs are connected with the positive direct current of +48 v, and the pair 3-6 of twisted pairs are connected with the negative direct current, such that the two pairs 1-2, 3-6 of twisted pairs are used for power supply and transmitting Ethernet signals;
• the remote-end user unit comprises a power over Ethernet (POE) power supply unit, which extracts direct current power from the two pairs 1-2, 3-6 of twisted pairs, and provides power supply for each unit of the remote-end user terminal after the direct current conversion from +48 v to +5V.