CN1164060C - Method and apparatus for communication using pulse decoding - Google Patents

Abstract

A signal in any physical form, which corresponds to an information character for coding an alphabet, is used as an analog waveform (the waveform is cycled in a character rate period) of a defined symbol to be transmitted to a communication channel. Subsequently, when the signal is received by a receiver, the signal is converted into many groups of pulses with silence separation, wherein each group of pulses is mapped into a count corresponding to the character for coding an alphabet. The pulse groups are separated in silence in arbitrary duration time, and the duration time is larger than the time between single pulses. The pulses have pulse speed which is larger than symbol frequency. The system permits rather than requires the communication of correspondingly narrow bandwidth signals.

Description

Use the communication means of pulse decoding

Background technology

The present invention relates to the communication between transmitter and receiver, undertaken by channel.It can be applied to telecommunications, record, storage and control.

Along with development of electronic technology, determined that sending radiofrequency signal with modulating frequency on wide spectrum is possible and practical, this wide spectrum comprises from the infrasonic frequency frequency to microwave frequency range.Yet, also do not have a kind of modulation and demodulation technology of this ability of utilizing to occur so far.

Summary of the invention

According to the present invention, corresponding to the signal of any physical form of coded word matrix information character is that analog waveform (this waveform is with the character rate loop cycle) as define symbol sends to communication channel, and subsequently when signal is received the machine reception, this signal just is converted to many groups by the pulse of mourning in silence and separating, and wherein every group pulse is mapped as the counting corresponding with the alphabetic characters of encoding.These pulse groups are by the separation of mourning in silence of any duration, and this duration is greater than the time between the independent pulse.These pulses have the pulse rate of is-greater-than symbol frequency.This system allows but is not the communication of requirement relative narrower bandwidth signal.

The present invention is a kind of baseband modulation and direct demodulation method and related system.Its advantage is that it does not need complete sign or extracts symbol by receiver, thereby detector and decoder that can practical simple.And, do not need or notion that not applied information or carrier wave do not recover on carrier wave.The notion that equally, does not also have frequency inverted or in medium-frequency band, detect.

Whether the present invention not only can be applied to electromagnetism and send and receive, can also no matter relevant with any form of energy use.

Following detailed description reference in conjunction with the drawings just can be understood the present invention better.

Description of drawings

Fig. 1 is the block diagram according to communication system of the present invention.

Fig. 2 example be used to represent any analog waveform of symbol.

Fig. 3 explanation is corresponding to the pulse example of the waveform portion of discussing in conjunction with Fig. 2.

Fig. 4 is the rough schematic view according to receiver of the present invention.

Embodiment

Fig. 1 is the block diagram according to communication system 10 of the present invention.System 100 comprises transmitter 12 and the receiver 22 by channel 20 couplings.Transmitter 12 receiving data streams 14, and by output 16 transmission simulation output waveforms 18, this waveform is represented by symbol sebolic addressing form x (t).Channel 20 has been represented between transmitter and receiver all infringements of signal transmitted x (t), comprises noise.Therefore, provide following transmission mapping function:

y(t)＝f(x(τ)，t) (1)

Receiver 22 according to the present invention produces output or P (t) with pulse group form, and as described below, it will offer decision maker 26.Decision maker 26 reverts to data flow 14 ' with the expression of data flow 14.This can for example pass through to calculate the pulse in each group, and the step-by-step counting of each group pulse is mapped to the character of being set up by system character set.

With reference to Fig. 2, the sequence of symbol 18 is shown.Symbol 18 is a kind of analog waveforms arbitrarily, and it can be sine wave, oblique wave, sawtooth waveforms, square wave, asymmetrical wave or have the waveform that is optimized selected shape at the α priori characteristic of channel, or the combination in any of these symbols.Each symbol all uses information (for example may influence anything of shape, including, but not limited to amplitude, frequency, slope, phase place and their combination in any) to encode.

Symbol 18 is encoded by transmitter 12.Transmitter is with each information character or the letter of value and the symbol shape mapping that at least one offers channel 20 of character set.Between character and symbol, normally concern one to one.The simplest character set is binary system collection " 1 " and " 0 " or " very " and " vacation ", except that the physical constraints that every symbol figure place is applied by law of nature, to not restriction of the number of characters in the character set.Have many more characters in the character set, in face of noise, the robustness of given energy level is just low more.Character rate is for the pulse train that therefrom extracts, and is relatively slow usually.

With reference to Fig. 3, the expression according to pulse P of the present invention (t) group 24 is shown.Each sign map is given single group pulse 24.Like this, for the coding purpose, the speed that pulse generates must be greater than the speed of expection pulse generation.Duration of mourning in silence adds the duration 28 of pulse train duration corresponding to symbol.Yet mourning in silence is greater than independent any duration of time between the pulse.Like this, suppose to plan to decode in real time, every group pulse just can the random time in symbol duration begins or stops.Like this, the umber of pulse in each pulse group can be at an easy rate corresponding to by the pairing information character of the pulse train of symbolic representation, waveform 18 can have different mappings many and the certain pulses counting.This just can provide further robustness by coding redundancy.

With reference to Fig. 4, the basic circuit of receiver 22 is shown.It comprises two element Z 30 and Z _D32.The signal y (t) that signal source 34 representatives are received is expressed as voltage Vs at this.Output is P (t).Signal source 34 offers the first general normalized impedance element Z 30 with waveform, and it offers output the second general impedance Z successively _D32.First and second general impedance Z 30 and the Z _D32 combination results pulse train output P (t).Explain general formula with the voltage and current item:

V _D＝V _s-Z∫I _Ddt (2)

$\mathrm{\ϵ}\frac{{\mathrm{dI}}_D}{\mathrm{dt}}=V_D-\mathrm{\Ψ}\left(I_D\right)-------\left(3\right)$

Or

$Z\frac{{\mathrm{dI}}_D}{\mathrm{dt}}=V_s-V_D------\left(4\right)$

$\mathrm{\ϵ}\frac{{\mathrm{dV}}_D}{\mathrm{dt}}=I_D-\mathrm{\Ψ}\left(V_D\right)-------\left(5\right)$

Formula 4 and 5 is antithesis of formula 2 and 3.These formula have been described the curtage waveform to the direct conversion according to the pulse train of the suitable selection of ψ (.), and wherein ψ (.) is impedance component Z _DTransmission characteristic.ε is less disturbance parameter.

The present invention is illustrated in conjunction with specific embodiment.For those skilled in the art, other embodiment are clearly.Thereby except that accessory claim, the present invention is not limited to other forms.

Claims (4)

1, a kind ofly be used for method for communicating between transmitter and receiver, it is characterized in that, comprising:

Generation is corresponding to the analog waveform of coded word matrix information character, symbol of described waveform definition, and described waveform is with the character rate loop cycle;

The signal that receives in order to produce sends to described receiver by communication channel from described transmitter, and by information source and described symbol coupling that described waveform characterizes, described communication channel has the characteristic of channel that comprises noise; And

From described received signal, extract the information of pulse group form at described receiver place, described pulse is by the separation of mourning in silence greater than any duration of time between the independent pulse, wherein the umber of pulse in each pulse group is corresponding to by one of described information character of described symbology, and wherein said pulse has the pulse rate greater than described symbol frequency.

2, the method for claim 1 is characterized in that, described analog waveform is to select from the group of being made up of sine wave, oblique wave, asymmetrical wave, sawtooth waveforms, square wave and channel optimization symbol.

3, the method for claim 1 is characterized in that, described analog waveform comprises the mixing of different wave type, and described type comprises time dependent channel optimization symbol.

4, the method for claim 1 is characterized in that, described pulse has with respect to nonoscillating 0 to maximum peak to peak amplitude at least.

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