A kind of power-line carrier communication method
Technical field
The present invention relates to the power line carrier communication field, particularly a kind of power-line carrier communication method that sends at a high speed long numeric data at the power frequency zero crossing.
Background technology
Power line carrier communication is with the communication mode of high-frequency carrier signal by high pressure or low-voltage power line transmission information.Utilizing the power frequency zero crossing to carry out power line carrier transmission is a kind of common method, and major advantage is that the zero crossing switching noise is few.But at present, in the method for conventional powerline carrier wave power frequency zero crossing communication, only send a data at each zero crossing, as adopting the spreading code mode to explain a data or explaining a data with the waveform of different frequency.Such communication mode can only be applied in the occasion not high to the data rate requirement, if need to transmit the data of higher bandwidth, such as the both-way communication of intelligent grid, then is difficult to satisfy actual needs.
Summary of the invention
The present invention is directed at present, when utilizing the power frequency zero crossing to communicate in the power line carrier communication process, each zero crossing only transmits 1 bit data, and the deficiency that transmission bandwidth can not be satisfied the demand provides a kind of power-line carrier communication method that transmits long numeric data at each zero crossing.
The present invention for the technical scheme of finishing its technical purpose and adopting is: a kind of power-line carrier communication method, and the information source end is packaged into data cell with the data of data source, sends described data cell in the timeslice of power line power frequency zero crossing,
May further comprise the steps at the information source end:
The step that the digital signal of data cell is modulated;
The step that modulation signal is sent in the power frequency zero crossing timeslice;
May further comprise the steps at stay of two nights end:
Receive the step of modulation signal in the power frequency zero crossing timeslice;
The modulation signal demodulation that receives is obtained the step of the digital signal of data cell.
Further, in the above-mentioned power-line carrier communication method: the step that also comprises the information source coding at the information source end; The step that comprises corresponding decoding at stay of two nights end.
Further, in the above-mentioned power-line carrier communication method: described information source coding may further comprise the steps:
The step that data cell is encoded;
The step that adds synchronizing signal in the data behind coding.
Further, in the above-mentioned power-line carrier communication method: adding in the step of synchronizing signal in the data behind coding, is that synchronizing signal is joined coded data central authorities.
Further, in the above-mentioned power-line carrier communication method: also be included in the step that data both sides behind the coding add redundant code.
Further, in the above-mentioned power-line carrier communication method: the step that data cell is encoded is to adopt Manchester coding mode.
Further, in the above-mentioned power-line carrier communication method: described synchronizing signal is the combination of any at least three continuous " 0 " or three continuous " 1 ".
Further, in the above-mentioned power-line carrier communication method: described synchronizing signal is " 111000 " or " 000111 ".
Further, in the above-mentioned power-line carrier communication method: described modulation system is BFSK.
The present invention can at tens bits of single zero crossing transmission, can satisfy more transfer of data demand.
Below by specific embodiment by reference to the accompanying drawings the present invention is further detailed.
Description of drawings
Accompanying drawing 1, embodiment of the invention carrier signal figure.
The situation schematic diagram that receives when accompanying drawing 2, the drift of embodiment of the invention stay of two nights termination receiving end generation zero crossing.
Embodiment
The present embodiment is that each 1.5ms is as the zero-crossing timing sheet before and after choosing zero crossing, and length is 3ms.Example is being divided into 48 bits in the 3ms, every bit 62.5us, and middle 6 bits (000111) are as synchronous code.Each 16 bit is used for data before and after the synchronous code, adopts Manchester's code, and 01 represents 0,10 represents 1, and then respectively there are 8 Bit datas front and back.Remaining 10 bits are each 5 bit up front and backmost, is used for eliminating the zero crossing deviation that receives and send.Redundant data can be check code, must also represent with Manchester's code.
The effect of this example can be transmitted 1600Bps when the 50HZ alternating current, each 5 bit of front and back redundant data, the zero crossing deviation that can stand 5*62.5=312.5us.
Information source end concrete steps are as follows:
Data to be transferred is broken according to data unit of every 16bit;
Data to each data cell are carried out Manchester's code, and represent 0,10 and represent 1 this moment 01;
In the middle of the Manchester's code of each data cell, add " 111000 ", make the data of each 8bit of " 111000 " front and back;
The data both sides of each 8bit respectively add the redundant data of 5bit before and after " 111000 ";
Above-mentioned data are carried out the BFSK modulation;
Modulation signal is sent in the timeslice of the 3ms centered by the power frequency zero crossing.
As follows in stay of two nights end concrete steps:
In the timeslice of the 3ms centered by the power frequency zero crossing, receive the BFSK modulation signal;
The BFSK signal is carried out demodulation;
Obtain synchronous code " 111000 ";
Obtain each 8bit manchester encoded data of synchronous code both sides, every bit data are " 01 " or " 10 " two;
Carry out manchester decoder, obtain altogether 16bit data, and all data acquisition systems that will obtain are preserved.