CN201244156Y - Baby monitor - Google Patents
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- CN201244156Y CN201244156Y CNU200820301523XU CN200820301523U CN201244156Y CN 201244156 Y CN201244156 Y CN 201244156Y CN U200820301523X U CNU200820301523X U CN U200820301523XU CN 200820301523 U CN200820301523 U CN 200820301523U CN 201244156 Y CN201244156 Y CN 201244156Y
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Abstract
The utility model discloses a radiationless baby monitor which eliminates the potential effect of microwave radiation resulted by the prior baby monitor adopting radio transmission upon babies. A baby terminal and a parent terminal are connected though a power line, wherein the baby terminal comprises a video and audio pickup and coding device, a microprocessor, a bypass signal receiver controlled by the microprocessor, a carrier generator and a modulator which are controlled by the microprocessor, and a power line coupling circuit; and the parent terminal comprises a power line coupling circuit, a microprocessor, a bypass signal receiving and processing device, a video and audio demodulating and coding device and a video and audio player.
Description
Technical field the present invention relates to a kind of baby monitor device.
When background technology was stayed alone a Room as the baby, the head of a family can worry about and uneasy for the situation that can not recognize child at any time, for example cooked in the kitchen, other room sanitization or the like.The head of a family wishes to understand baby's situation always, for example, whether wakes up, crys, makes dangerous action or the like.
Baby monitor device on the market just can help the head of a family to remove this worry at present.
Present baby monitor device comprises head of a family's terminal and baby's terminal two parts, and two parts connect by radio.Baby's terminal is placed in baby's the room, and near the baby, it is made up of information pickup part and transmitting set two parts, and information pickup partly picks up baby's sound or image information, launches to aerial all directions via transmitting set.Head of a family's terminal is made up of radio receiver and information replay two parts, in the scope of emitter certain radius, radio receiver receives the signal that baby's terminal sends, and demodulates AV signal, is replayed by information and partly plays baby's video image or sound.
Because head of a family's terminal and baby's terminal be by radio connectivity, so even the head of a family at the even not same floor of chummery not, as long as with head of a family's terminal of last baby monitor device, just can to the baby dynamically not clearly.By this device, the head of a family just can handle other affairs Anywhere in families such as study, kitchen, can recognize child's situation simultaneously again at any time, and child's every act and every move is all had at fingertips, needn't be at every moment on tenterhooks again.The baby monitor device is used widely in the family of American-European countries.
But some scientists are recently to the widely-used worry of having represented of baby monitor device.They warn that this original idea is the monitor that is used for guaranteeing baby safe, and immature child is among the radiation.
In the ordinary course of things, the heads of a family can be placed on the place very near apart from the baby to baby's terminal of baby monitor device in order to observe clearlyer.Yet because child's health and nervous system also are in the stage of development, their health is subjected to radiating influence especially easily.
According to Britain's " independent newspaper " on May 20th, 2007, scientist represents, the baby monitor device of existing market, the same with wireless phone, what use all is that numeral strengthens wireless communication technology, therefore its frequency that sends signal is more than 1G,, these baby monitor devices also can send similar microwave radiation as wireless phone.The baby who is growing, its soma is " highstrung ".The radiating information service of a research mechanism then represents: " in the baby bedroom, place the microwave radiation that monitor caused, also bigger than near the radiation that stays in the antenna for mobile phone tower.”
Can see thus, be that child has removed observable danger though wireless baby monitor device makes the head of a family, therefore virtually may be for child has added invisible, a potential danger, even may have influence on the normal growth promoter of child.
The summary of the invention the purpose of this utility model is the deficiency that overcomes existing baby monitor device, the radio radiation influence of the transmitter of baby's terminal of release baby monitor device, and the protection baby's is healthy.
For solving the technical problem of above-mentioned existence, the technical solution of the utility model is:
1, a kind of baby monitor of eliminating baby's radiation hidden danger comprises baby's terminal, electric lines of force, head of a family's terminal;
A) signal output part of said baby's terminal is the alternating current power supply jack that directly inserts electric lines of force;
B) signal input output end of said head of a family's terminal is the alternating current power supply jack that directly inserts electric lines of force;
C) baby's terminal and head of a family's terminal interlink by electric lines of force, and the audio or video signal that baby's terminal is obtained is modulated onto on the carrier wave, and carrier wave is sent on the electric lines of force, and head of a family's terminal reception carrier from the electric lines of force demodulates the audio or video signal and resets.
2, above-mentioned baby's terminal includes:
The electric lines of force coupling circuit is used for carrier signal with baby's terminal and is coupled on the electric lines of force and with the carrier signal on the electric lines of force and is coupled to baby's terminal;
Band filter is used for that the signal from electric lines of force is carried out frequency-selecting and amplifies, to measure the signal to noise ratio of each frequency on the electric lines of force;
Microcontroller is used to control the mid frequency of band filter, measures the signal to noise ratio of each frequency on the electric lines of force, according to the signal to noise ratio of each frequency on the electric lines of force, determines and the frequency of the control carrier wave that carrier generator produced;
By the audio or video acquisition cuicuit that mike or photographic head constitute, be used to obtain baby's sound or picture signal;
At least one carrier generator is used to produce the baby's that transmission obtains sound and picture signal at least one carrier signal to the electric lines of force;
At least one manipulator is used for sound and image signal modulation to carrier wave.
3, above-mentioned head of a family's terminal includes:
The electric lines of force coupling circuit is used for the carrier signal on the electric lines of force is coupled to head of a family's terminal;
At least one band filter is used for that the signal from electric lines of force is carried out frequency-selecting and amplifies;
Microcontroller is used to control the mid frequency of band filter, determines the frequency of carrier signal;
At least one demodulator is used for sound or picture signal are come out from the carrier wave demodulation;
Audio frequency amplifies or image processing circuit, is used for sound that demodulation is come out and picture signal to handle and reset.
4, above-mentioned electric lines of force coupling circuit is made up of a high frequency transformer and a capacitances in series, and electric capacity is used to block the low frequency signals such as power supply signal of 50HZ or 60HZ, and allows the carrier signal of upper frequency pass through; High frequency transformer is used to allow the carrier signal of upper frequency by block the power supply signal of 50HZ or 60HZ, and the electric supply that passed through transformer isolation.
The frequency of the carrier signal by power line transmission is between 60k～200kHz.
Baby's terminal is inserted in the supply socket between infant room, and head of a family's terminal can be inserted in the supply socket in room, current head of a family place.The signal of baby's terminal just passes on the parent terminal along electric lines of force.
The invention has the beneficial effects as follows that at baby's end, the transmission of signal does not adopt radio to aerial transmission, just transmit, and the frequency of carrier wave is very low, below 200KHz along electric lines of force, thereby baby end do not produce radiation, eliminated the potential impact to infantile health
Appended drawings 1 is the schematic diagram of baby's terminal of baby monitor device
Accompanying drawing 2 is schematic diagrams of head of a family's terminal of baby monitor device,
Accompanying drawing 3 is the variable band filters of mid frequency,
Accompanying drawing 4 is electric lines of force coupling circuits,
Accompanying drawing 5 is carrier generator and manipulator,
Accompanying drawing 6 is structure charts of baby monitor device.
The utility model will be further described below in conjunction with drawings and Examples for specific implementation method.1,2 and 6, one baby monitor device comprises baby's terminal and at least one head of a family's terminal with reference to the accompanying drawings.
Baby's end among Fig. 1 comprises mike 1, amplifier 2, manipulator 3, electric lines of force coupling circuit 4, attaching plug 5, the band filter 6 that mid frequency is variable, carrier generator 7, microprocessor 8.
Among Fig. 1, mike 1 detected sound after amplifier 2 amplifications, enters manipulator 3 modulation, and synthetic carrier wave is produced under microcontroller 8 controls by carrier generator 7.Carrier signal is admitted to electric lines of force at last through overcoupled circuits, and the 5th, attaching plug inserts in the supply socket.
On the electric lines of force because follow various consuming device, for example various motors, Switching Power Supply, controllable silicon power governor or the like, and long electric lines of force also is very easy to be coupled to various interference, therefore, has frequency spectrum noise widely on the electric lines of force; The consuming device that while power does not wait can make the equiva lent impedance of electric lines of force very low, greatly between 1 ~ 20 Europe.Thereby the signal transmission conditions on the electric lines of force are actually very severe, if in the frequency range of above-mentioned 60 ~ 200k carrier wave, arbitrarily selected frequency just transmits, and are the effects that is difficult to guarantee transmission.
The present invention adopts that the frequency of optimum signal-noise ratio transmits on the electric lines of force.The optimum signal-noise ratio frequency is by mid frequency variable band filter and microprocessor, determines in order to following method searching.
The detailed principle of the band filter among Fig. 1 is in Fig. 3.Signal is come in from the A point, from the output of B point, through the built-in A/D changer of microprocessor, enters microprocessor, and three operational amplifiers 27,29,30 constitute band filter, and according to relevant rules, carrier frequency will be between 60k ~ 200K.The switch of microprocessor 8 control variable connectors 28,31 changes the resistance of loop, thereby changes the mid frequency of band filter, and variable connector can adopt 74HC4052.On the electric lines of force, the different frequency that distributing, the various noises that amplitude is different can produce ill effect to the transmission of signal, and the signal to noise ratio that must try every possible means to improve the power line transmission channel could realize utilizing the power line transmission signal smoothly.Method of the present utility model is that microprocessor control variable connector is in diverse location, for example 4 positions, making the mid frequency of band filter be positioned between 60K ~ 200K, is respectively F1, F2, F3, F4, microprocessor read in the magnitude of voltage N1 that B is ordered under each mid frequency, N2, N3, N4, Here it is electric lines of force is at F1, F2, F3, the noise amplitude on F44 frequency.Then, in Fig. 5, microprocessor control variable connector 36 changes resistance value, thereby the frequency of carrier signal that makes phase-locked loop pll 35 produce is respectively F1, F2, and F3, F4, according to Fig. 1, carrier signal enters electric lines of force through coupling circuit.Meanwhile, among Fig. 5, the mid frequency of microprocessor 8 control band filters is respectively F1, F2, and F3, F4, and microprocessor reads in the magnitude of voltage that B is ordered under each frequency, S1, S2, S3, S4.Obviously, these magnitudes of voltage are directly proportional with signal amplitude.Microprocessor calculates the Si/Ni value under each frequency, (i=1,2,3,4).The pairing frequency of Si/Ni numerical value maximum is exactly the channel of current signal to noise ratio maximum.The microprocessor of baby's terminal just sends carrier wave at the frequency of current signal to noise ratio maximum, the frequency that sends carrier wave has been determined like this, this carrier frequency can be avoided noise and low-impedance influence on the electric lines of force to greatest extent, and ensureing has best reception.
The transmission frequency of this best both can be static, also can be dynamic.So-called static, be meant that in the use that once powers on baby's terminal just adopts this frequency to send once determining that certain frequency is best frequency down always, no longer changes.Dynamically being meant, is that best frequency sends signal even determine certain frequency, microprocessor still at regular intervals after, repeat the method for the best frequency of above-mentioned search, find out the frequency of current the best, and send at current best frequency.
The audio signal that baby's terminal collects will be by in the FM mode, is modulated on the carrier wave that said method determines.Adopting well-known phaselocked loop FM to modulate realizes.Phase Lock Loop IC adopts 74HC4046, and the direct outgoing carrier of microprocessor enters the phase bit comparison end of phaselocked loop, and the mid frequency of phaselocked loop equates with carrier frequency.
Fig. 5 is that the carrier wave of baby's terminal generates and audio frequency FM modulating part, mainly by microprocessor 8, and phase-locked loop pll 35, adder 34, variable connector 36 constitutes.After microprocessor has been determined the frequency of carrier wave according to above-mentioned steps, just select a certain road of variable connector 36, the resistance on this road and the electric capacity of 4700P have been determined the mid frequency of phaselocked loop, the just frequency of carrier wave jointly.The signal of the direct outgoing carrier frequency of microprocessor, voltage controlled oscillator VCO with phaselocked loop is exported the phase comparator that enters phaselocked loop, after the output of the phase comparator of phaselocked loop is made low-pass filtering through the RC circuit, the audio signal of amplifying with the mike collection and through amplifier is in adder 34 additions, send into the voltage controlled oscillator VCO input of PLL again, the outfan of VCO is exported, and is exactly the carrier signal that audio signal FM has been modulated on the optimum channel.
In the modulated process of audio signal, every a specific time, for example 60 seconds, stop the modulation of audio signal, coming modulated carrier and send a string synchronous code, for example is that 256 101010 train of pulse constitutes synchronous code, and the width of pulse is 1ms, therefore, the persistent period of train of pulse is 256 milliseconds.Synchronous code only took 256ms in 60 seconds, to the transmission of audio frequency, almost have no effect.Modulation sends after the synchronous code, and modulation sends audio signal again again.Synchronous code is used for the identification of the employed frequency of ripple that head of a family's terminal carries baby's terminal and judges.
The modulated carrier signal enters the D end as the coupling circuit among Fig. 4 after power amplification.
The generation of carrier wave and amplifier section all belong to light current, and finally it will be admitted to the electric lines of force of forceful electric power.So, must some circuit be born the function that connects light current and forceful electric power, Here it is coupling circuit.On the one hand, it wants the influence of the forceful electric power source of big high attenuation or even blocking-up electric lines of force to weak electrical loop, and the carrier signal that allows weak electrical loop produce simultaneously again is sent in the forceful electric power loop undampedly.Suitably the electric capacity of capacitance can be born this work, it to 50 or the forceful electric power source voltage of 60Hz present very high impedance, and the carrier signal of relative 60～200kHz then presents very low impedance.Strengthen this effect for further, and more can make forceful electric power and light current isolate, can add a high frequency transformer.
As Fig. 4, coupling circuit is made up of high frequency transformer 33 and electric capacity, and electric capacity is used to block the low frequency signals such as power supply signal of 50HZ or 60HZ, and allows the carrier signal of upper frequency pass through; High frequency transformer is used to allow the carrier signal of upper frequency by blocking the power supply signal of 50HZ or 60HZ.Like this, carrier signal is coupled on the electric lines of force of C end, and, by transformer isolation electric supply.
Here, the appearance value of electric capacity is 0.047u, transformator are on the magnet ring of diameter 1cm, and be elementary, secondary all separately around 20 circles.
So, in the process that the carrier signal of audio frequency sends, do not use radio, thoroughly exempted the influence of radio radiation the baby.
As baby's terminal, in head of a family's terminal, coupling circuit must be arranged equally connecting electric lines of force and head of a family's terminal, the influence of blocking-up electric supply, and allow carrier signal pass through smoothly, its structure and parameter is as baby's terminal.
Carrier signal is after entering head of a family's terminal on the electric lines of force, how does head of a family's terminal receive and obtains? which frequency does how head of a family's terminal learn baby's terminal adopts send carrier wave? supposition as an example, arrange between baby's terminal and the head of a family's terminal, carrier signal only adopts above-mentioned F1, F2, F3, one among 4 frequencies such as F4 sends, after head of a family's terminal is inserted into the electric lines of force socket and powers on, and the mid frequency of the microprocessor control alterable band-pass filter of head of a family's terminal, make it be respectively F1, F2, F3, F4, reception carrier signal all on each frequency respectively, and to the carrier signal demodulation.Receive the local oscillation signal that adopts well-known superhet mode, microprocessor directly to export under the current carrier wave and give the superhet amplifier.The frequency FL of local oscillation signal, the frequency F of carrier signal, satisfy following relation between the IF-FRE FI three: F+FL=FI. IF-FRE FI, get numerical value, for example a 455KHz regularly.The mid frequency of controlling band filter when microprocessor is respectively F1, F2, F3 is during F4, correspondingly, the local oscillator of microprocessor output should be respectively 455-F1 just, 455-F2,455F3, the some transmission frequency of 455F4., by the mid frequency and the local frequency of the band filter of microprocessor control, determine jointly.Promptly be that the band filter mid frequency equals carrier frequency, local frequency equals 455 poor with carrier frequency.
Whether the audio signal that microprocessor search demodulation is come out has successive is the 1ms train of pulse near 256 pulse widths, after it has searched this synchronous code, has just determined that baby's terminal is to have sent carrier wave on this frequency.Microprocessor after this searches synchronous code, every 60 seconds with 250 milliseconds of the audio mute of demodulator output, and search for synchronous code once more.Because quiet, so the audio frequency people ear that the synchronous code train of pulse causes is unheard.If on this frequency, search is less than synchronous code, and microprocessor is just controlled the mid frequency of band filter, and the frequency of local oscillator, changes next carrier frequency and goes to continue search.Like this, no matter baby's terminal is to adopt dynamic or static best frequency to send, and head of a family's terminal can both capture this frequency, and continues received signal on this frequency.
In head of a family's terminal of the baby monitor device of Fig. 2, contain attaching plug 9, coupling circuit 10, the band filter 11 of variable center frequency, superhet amplifier 27, demodulator 12, audio-frequency power amplifier 13, loudspeaker 14.
The 9th, attaching plug, be inserted in the electric lines of force socket, carrier signal on the electric lines of force is through plug 9, enter coupling circuit 10, same, coupling circuit as shown in Figure 4, signal enters from the C end, be coupled to the D end, enter into band filter, as shown in Figure 5, the mid frequency of band filter is controlled by microprocessor 15, microprocessor changes the mid frequency of band filter one by one, is respectively F1, F2, F3, F4, and one by one directly output frequency be 455-F1,455-F2,455-F3, the local oscillation signal of 455-F4 is given superhet amplifier 27, and in output place of FM demodulator, microprocessor detects audio signal, microprocessor search this moment synchronous code, if obtain baby's synchronous code that terminal sends, head of a family's terminal just captures the frequency of the carrier wave of baby's terminal transmission so, and the mid frequency of microprocessor control band filter is in this frequency always, and the local frequency that it exports to the superhet amplifier also is in this frequency always, just continue to receive the audio signal of baby's terminal, audio signal is amplified through amplifier 13, emits sound at loudspeaker 14.
If the baby monitor device will transmit video signal, its structure and operation principle and aforesaid baby monitor device basically identical.Difference is: baby's terminal is not single only gathers audio signal with mike, more use camera collection video signal and digitized, and need do the D/A conversion again at the digital video signal that the demodulation of head of a family's terminal is come out, become analog video signal, little LCDs of reuse or CRT guard and play, and this is well-known.
The another one difference is, if because the data volume that video transmits can be more much bigger than transmitting audio frequency, transmit more multidata requirement for satisfying, can in the frequency range that transmits, satisfy under the condition of certain bandwidth granularity, marking off more frequency, simultaneously, determining in the step of best carrier frequency in aforementioned baby's terminal, is preface according to the size of signal to noise ratio, determines a plurality of preferable transmission frequencies in turn.For example, have 8 and send frequency, get the highest three frequencies of signal to noise ratio after the measurement and send data as preferable transmission frequency, all data that microprocessor will transmit, be divided into three parts, send the carrier wave of different frequency on three different frequent points simultaneously, the speed that sends data so is just than only using a frequency to improve 3 times.Head of a family's terminal just has three mid frequency alterable band-pass filters, three superheterodyne reception amplifiers, head of a family's terminal receiving course as above-mentioned single frequency point, microprocessor search synchronous code, determine 3 frequencies of the current use of baby's terminal after, on 3 frequencies, receive data simultaneously.Synchronously, microprocessor synthesizes back this received three partial data according to the fractionation standard of original baby's terminal the video data of original integral body again.Video data is finally by playback.
Claims (3)
- [claim 1] a kind of baby monitor device is characterized in that comprising baby's terminal, electric lines of force, head of a family's terminal;The signal output part of A, said baby's terminal is the alternating current power supply jack that directly inserts electric lines of force;The signal input of B, said head of a family's terminal is defeated to be the alternating current power supply jack that directly inserts electric lines of force;C, baby's terminal and head of a family's terminal interlink by electric lines of force, and the audio or video signal that baby's terminal is obtained is modulated onto on the carrier wave, and carrier wave is sent on the electric lines of force, and head of a family's terminal reception carrier from the electric lines of force demodulates the audio or video signal and resets.
- [claim 2] baby monitor device according to claim 1, it is characterized in that said baby's terminal includes: the electric lines of force coupling circuit is used for carrier signal with baby's terminal and is coupled on the electric lines of force and with the carrier signal on the electric lines of force and is coupled to baby's terminal;Band filter is used for that the signal from electric lines of force is carried out frequency-selecting and amplifies, to measure the signal to noise ratio of each frequency on the electric lines of force;Microcontroller is used to control the mid frequency of band filter, measures the signal to noise ratio of each frequency on the electric lines of force, according to the signal to noise ratio of each frequency on the electric lines of force, determines and the frequency of the control carrier wave that carrier generator produced;By the audio or video acquisition cuicuit that mike or photographic head constitute, be used to obtain baby's sound or picture signal;At least one carrier generator is used to produce the baby's that transmission obtains sound and picture signal at least one carrier signal to the electric lines of force;At least one manipulator is used for sound and image signal modulation to carrier wave.
- [claim 3] baby monitor device according to claim 1 is characterized in that said head of a family's terminal includes:The electric lines of force coupling circuit is used for the carrier signal on the electric lines of force is coupled to head of a family's terminal;At least one band filter is used for that the signal from electric lines of force is carried out frequency-selecting and amplifies;Microcontroller is used to control the mid frequency of band filter, determines the frequency of carrier signal;At least one demodulator is used for sound or picture signal are come out from the carrier wave demodulation;Audio frequency amplifies or image processing circuit, is used for sound that demodulation is come out and picture signal to handle and reset.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU200820301523XU CN201244156Y (en) | 2008-07-16 | 2008-07-16 | Baby monitor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU200820301523XU CN201244156Y (en) | 2008-07-16 | 2008-07-16 | Baby monitor |
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| CN201244156Y true CN201244156Y (en) | 2009-05-27 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU200820301523XU Expired - Fee Related CN201244156Y (en) | 2008-07-16 | 2008-07-16 | Baby monitor |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104822054A (en) * | 2015-04-27 | 2015-08-05 | 寅家电子科技（上海）有限公司 | Transmitting device, receiving device and system adopting power line to transmit audio and video signals |
| CN105788224A (en) * | 2016-02-15 | 2016-07-20 | 黄焕珠 | Control device for household power line carrier |
-
2008
- 2008-07-16 CN CNU200820301523XU patent/CN201244156Y/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104822054A (en) * | 2015-04-27 | 2015-08-05 | 寅家电子科技（上海）有限公司 | Transmitting device, receiving device and system adopting power line to transmit audio and video signals |
| CN105788224A (en) * | 2016-02-15 | 2016-07-20 | 黄焕珠 | Control device for household power line carrier |
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Granted publication date: 20090527 Termination date: 20100716 |