CN100586054C

CN100586054C - Generator for generating random seed of channel sharing network

Info

Publication number: CN100586054C
Application number: CN200710113976A
Authority: CN
Inventors: 洪利
Original assignee: China University of Petroleum East China
Current assignee: China University of Petroleum East China
Priority date: 2007-10-24
Filing date: 2007-10-24
Publication date: 2010-01-27
Anticipated expiration: 2027-10-24
Also published as: CN101179368A

Abstract

The invention discloses a method and a generator for generating a random seed in a channel sharing network. The invention is applied to solve the problem that the random seeds are identical or have poor relativity in the prior art. The method is as follows: counting with a counter the number of pulses generated by the clock generator within the length of a data frame; wherein, the clock generator has a frequency which is two times or more than two times higher than the frequency of a data signal. The generator includes a heavy triggering mono-stability trigger, a mono-stability trigger, a clock generator and a counter. By adopting the structure and method, the measurement results of the same data frame are not completely same, as nodes have different physical locations in the network and different hardwires. Namely, random seeds of the network nodes are not identical. In addition, as all the network nodes measure the width of the same data frame, and the results have relativity.

Description

The random seed of channel sharing network generator

Technical field

The invention belongs to and relate to a kind of communication network technology field, be specifically related to method and generator that a kind of random seed made from IC regime that is used for channel share network produces.

Background technology

It is one of core technology of channel share networks such as wireless sensor network, wireless self-organization network, power carrier network, bus network that algorithm is avoided in conflict.Avoiding algorithm that suitable random seed is provided for conflict is to improve Channel Sharing efficient to avoid the key of efficient with conflicting.

Domestic disclosed random number seed acquisition methods has following several: a kind of is to write fixed data as random seed by the network node software programming, and the random seed of all nodes is identical in the network, can reduce conflict like this and avoid efficient; Another kind is the seed that adopts randomizer to produce, and the random seed of all nodes differs greatly in the network like this, and the random seed correlation is poor between network node, can reduce Channel Sharing efficient like this.

Summary of the invention

For overcoming above-mentioned defective, the object of the present invention is to provide a kind of not only incomplete same but also have correlation networks node randomizer.

For achieving the above object, the method that a kind of random seed of channel sharing network of the present invention produces is: with the number of counter calculating in the length pulse that internal clock generator produces of a Frame, wherein, clock generator is the clock generator that a frequency equals 2 times of frequency data signals or 2 above integral multiples.

Further, above-mentioned method is specially:

1) receives data-signal with can heavily triggering monostable flipflop, and under it triggers, produce transient state high level pulse and output that pulse duration is a Frame length;

2) produce the clock signal that a frequency equals 2 times of frequency data signals or 2 above integral multiples with clock generator, for counter provides counting clock;

3) counter clock to clock generator in the Frame length cycle is counted, and the result is the random seed of this node.

To achieve the above object of the invention, random seed of channel sharing network generator of the present invention comprises and can heavily trigger monostable flipflop, monostable flipflop, clock generator sum counter;

Can trigger heavily that monostable flipflop is used for producing pulse duration under the triggering that receives data-signal is the transient state high level pulse of Frame length, and exports counter and monostable flipflop to;

Monostable flipflop produces the transient state low level pulse, and exports the clear terminal of counter under the triggering of the transient state high level pulse rising edge that can heavily trigger monostable flipflop output, be used for counter O reset;

Clock generator is used to produce the clock signal that a frequency equals 2 times of frequency data signals or 2 above integral multiples, for counter provides counting clock;

Counter is counted the clock of clock generator, the zero clearing of counter is subjected to the startup of monostable flipflop output result control, counter and stops to be subjected to repeating monostable flipflop output result to control, can heavily trigger monostable flipflop output high level and make rolling counters forward, output low level that counter is kept, the retention value of counter is the random seed of this node.

Wherein, above-mentioned clock generator comprises that 555 integrated circuits make.

After adopting above-mentioned structure and method because the physical location of node in network is different and node have a hardware differences, so can be not identical to the measurement gained result of same Frame, promptly the random seed of each node of network can be not identical; Because all nodes of network carry out width measure to same frame data, the result has correlation again.Avoid the Channel Sharing efficient of algorithm and conflict to avoid efficient higher as the conflict of random seed.

Description of drawings

Fig. 1 is that random seed of channel sharing network generator of the present invention constitutes block diagram.

Fig. 2 is random seed of channel sharing network generator physical circuit figure.

Fig. 3 is the output waveform of each part.

Embodiment

Below in conjunction with drawings and Examples method and the generator that random seed of channel sharing network of the present invention produces is further described.

The method that a kind of random seed of channel sharing network of the present invention produces is: with the number of counter calculating in the length pulse that internal clock generator produces of a Frame, wherein, clock generator is the clock generator that a frequency equals 2 times of frequency data signals or 2 above integral multiples.

Further, above-mentioned method is specially:

2) with clock generator in producing the clock signal that a frequency equals 2 times of frequency data signals or 2 above integral multiples, for counter provides counting clock;

In the said method, it is fixed that frequency that clock generator produced and the multiple of frequency data signal relation can be come according to the concrete condition of network, and multiple is big more, and correlation is poor more, can improve conflict and avoid efficient, but can reduce Channel Sharing efficient; Multiple is more little, and correlation is strong more, can improve Channel Sharing efficient, avoids efficient but can reduce conflict; Therefore it is fixed to come in conjunction with the concrete condition of network.

Above-mentioned method, the hardware that is based on the different and node of the physical location of node in network there are differences, so can be not identical to the measurement gained result of same Frame, and promptly the random seed of each node of network can be not identical; Because all nodes of network carry out width measure to same frame data, the result has correlation again.Avoid the Channel Sharing efficient of algorithm and conflict to avoid efficient higher as the conflict of random seed.

Below in conjunction with accompanying drawing random seed of channel sharing network generator of the present invention is described.

Fig. 1 has shown a random seed generator block diagram, comprises that a signal shunt 200, one can heavily trigger monostable flipflop 300, monostable flipflop 400, a clock generator 500 and a counter 600.

200 function is along separate routes, and one road signal is divided into two-way, and signal waveform such as Fig. 3 are 1..300 function is that a frame data signals is become a transient state high level pulse, waveform such as Fig. 3 2., control counter work.400 function is for becoming the 300 transient state high level rising edges that produce into the low level transient signal, waveform such as Fig. 3 3., control counter 600 zero clearings.500 function is to produce counting clock, and 4. waveform such as Fig. 3 count for counter 600.600 function is to produce random seed, is subjected to 300 output controls, clock is counted the width decision rolling counters forward value of 300 transient state pulse high level, i.e. random seed.

The signal of signal shunt 200 after with the node demodulation is divided into two-way, and one the tunnel offers modal processor, and one the tunnel is input to and can heavily triggers monostable flipflop 300.Can heavily trigger monostable flipflop 300 and produce the transient state high level pulse, its transient state pulse duration is Frame length.300 outputs divide two-way, and one the tunnel is input to the rising edge of monostable flipflop 400,300 transient state pulses through 400 generation low level transient state pulses, to counter 600 zero clearings.Another road is input to counter 600 control counter operating states.It is the clock of 3 times of frequency data signals that clock generator 500 produces frequency, is defeated by counter 600 as counting clock.Counter 600 is subjected to heavily to trigger the control of the output of monostable flipflop 300, and when 300 output high level counters 600 pairs of clocks are counted, when output 300 low levels keep count results, this result is promptly as the random seed of this node.

Fig. 2 is the physical circuit figure that adopts the integrated circuit realization random seed generator of corresponding function.Signal shaping splitter 200 adopts integrated NAND gate 74LS00 to realize.

Can heavily trigger monostable flipflop 300 adopts integrated circuit 74LS122 to realize.

Monostable flipflop 400 adopts integrated circuit 74LS121 to realize

Because the clock generator 500 that ic 555 is made is simple in structure, and better performances, clock generator therefore of the present invention adopts ic 555 to cooperate resistance and electric capacity to form multivibrator and realizes.

Counter 600 adopts integrated circuit 74LS161 to realize.

Claims

1, a kind of random seed of channel sharing network generator is characterized in that: comprise and can heavily trigger monostable flipflop, monostable flipflop, clock generator sum counter;

Can heavily trigger monostable flipflop and under the triggering of data-signal, produce the transient state high level pulse that pulse duration is a Frame length, and export counter and monostable flipflop to;

Counter is counted the clock of clock generator, the zero clearing of counter is controlled by monostable flipflop output result, the startup of counter and stop to be subjected to heavily to trigger monostable flipflop output result and control, can heavily trigger monostable flipflop output high level and make rolling counters forward, output low level that counter is kept, the retention value of counter is the random seed of this node.