CN201349213Y

CN201349213Y - Cell phone signal interference shielding device realized through DDS

Info

Publication number: CN201349213Y
Application number: CNU2008202295430U
Authority: CN
Inventors: 黄国荣
Original assignee: Fujian Sunnada Communication Co Ltd
Current assignee: Fujian Sunnada Communication Co Ltd
Priority date: 2008-12-25
Filing date: 2008-12-25
Publication date: 2009-11-18
Anticipated expiration: 2018-12-25

Abstract

The utility model relates to a cell phone signal interference shielding device realized through DDS, which comprises a system former stage and a system later stage, and is characterized in that the system former stage is characterized in that DDS low frequency signals are driven to be output through an MCU, and generated DDS low frequency output signals can be transmitted through two paths, one path is coupled directly through a coupler, and then is simplified and output through a final amplifier, the other path passes through a radio frequency switch, the signals are switched stochastically by the high speed radio frequency switch to generate the signals which are changed stochastically, then are output through the final amplifier, the output signals are transmitted to the system later stage, the system later stage mainly couples the DDS signals generated by the front stage to the high frequency 930-960 MHz, then the signal strength of the signals is adjusted through a one stage controllable PA, thereby realizing carrying out the flexible and controllable shielding function in a certain range to cell phone signals under the condition of no affection to electronic devices and combining the high speed DDS signal generating principle and matching with a radio frequency module.

Description

The mobile phone signal interference shielding device that DDS realizes

Technical field

The utility model relates to contemporary mobile communication equipment mobile phone signal to be disturbed, and mainly is technology and the equipment about how under specific environment the mobile communication mobile phone signal effectively to be disturbed and to shield.

Background technology

Along with the fast development of mobile communication technology, mobile communication equipment particularly mobile phone becomes an indispensable part in the current social life of people especially in modern society.International Telecommunications Union said that world telephone subscriber quantity had reached 4,000,000,000 on September 4th, 2008, was 4 times before 10 years, and wherein the fixed telephone subscriber 12.7 hundred million, and the cellphone subscriber 26.8 hundred million.The research report that the IE Market Research of market research agency (IEMR) is up-to-date being entitled as of delivering " first quarter in 2008 moving projection: 2007-2010 Chinese market " points out that China Mobile's number of users will continue to increase fast the coming years.By 2010, Chinese cellphone subscriber's quantity will from 2007 5.40 hundred million rise to 7.38 hundred million.We can conclude that As time goes on these data will present the trend of growth.

Undeniable, as the mobile phone of one of current great invention,,, along with constantly the popularizing and using of mobile phone, correspondingly also produced a series of social concerns then for huge contribution is made in the development of society for people's social life provides huge facility.From abstract summary, it at first is individual's problem free time that these problems have, and you do not know that your boss will give you phone 1:00 AM or at 2; Next privacy problem, the increasing function of mobile phone provides means cheap, that be easy to get for exposing individual privacy; Be the personal lifestyle space problem once more, in actual life, perfectly combination somethings can only be found by accident, and not through seeking after all, and a lot of people need compensate with different living space, and mobile phone is the saboteur of this state; Or the like also have the idea sovereignty, have no right problem such as control.Analyze from particular problem, in the society that current cell phone apparatus is full of, the first, function mobile phone has from strength to strength become sharp weapon of examinee examination hall cheating; The second, the serious in the past meeting room meeting of today ringing sound of cell phone that invariably accompanies sounds again and again and carries out; The 3rd, the microwave signal of mobile phone is disturbed malignant fire and the explosion accident that often causes gas station, oil depot.The 4th, hospital was patients' the place that sets aside one's worries and have a good rest originally, and the ringing sound of cell phone that rises one after another has then allowed people be unequal to it and disturbed; The 5th, the library no longer has been the quiet environment of reading, learning; The 6th, when film plot just entered climax, audience was had to stand the bystander and is no end done marathon talk on the phone; Also has the military secrecy problem or the like that leaks.

The mobile handset device principle is exactly that mobile phone is converted to digital model to sound and is transmitted into the base station, forward on the mobile phone that you dial by the base station again, the other side's mobile phone converts digital signal to sound and so just realizes having conversed, specifically the communication process of mobile phone just is to use mobile phone that speech signal is transferred in the mobile communications network, by mobile communications network speech signal is become electromagnetic spectrum again, be sent in callee's the communication network by communication satellite radiation roaming, callee's communication equipment receives radio magnetic wave, converts speech signal to and connects communication network.Therefore, mobile communication is the electronic communication system of an opening, as long as corresponding receiving equipment is arranged, just can intercept and capture any time, any place, receives your call-information.

Summary of the invention

The purpose of this utility model provides the mobile phone signal interference shielding device that a kind of DDS realizes, it is implemented in not under the situation that other electronic equipments are exerted an influence, and produces the theoretical radio-frequency module that cooperates in conjunction with the high-speed DDS signal and mobile phone signal is carried out the shielding action of the flexible and controllable of certain limit.

The utility model is to realize like this, the mobile phone signal interference shielding device that a kind of DDS realizes, comprise before the system and level after the system, it is characterized in that: described system prime drives the output of DDS low frequency signal by MCU, the DDS low frequency output signal that produces can be sent through two passages, one the tunnel is directly through the coupler coupling, then through final stage amplifier tube amplification output; Another road is by radio-frequency (RF) switch, by the high-speed radio-frequency switch this signal is switched at random producing the signal of change at random, and then exports via the final stage amplifier tube; The signal of output is admitted to level after the system, and level mainly is that the DDS signal that prime produces is coupled to high frequency 930～960MHZ after the described system, adjusts this signal strength signal intensity by the controllable PA of one-level then.

The utility model mainly is to adopt microcontroller chip MCU and DDS high speed signal to produce to be used for the low frequency signal source that signal disturbs, add the high frequency mixing of peripheral radio-frequency module simultaneously and reach the mobile phone of standard and the signal of communication of base station, interference handset is to the decoding of base station signal, thereby the transmitting power of controlling interference source equipment is simultaneously again controlled interference range to avoid the influence to base station signal or other electronic equipments.

Description of drawings

Fig. 1 is the utility model embodiment system prime theory diagram.

Fig. 2 is a level theory diagram after the utility model embodiment system.

Embodiment

Below in conjunction with drawings and Examples the utility model is described further.

The course of work of mobile phone signal shielding be with certain speed from the low side frequency of forward direction channel to high-end scanning, this sweep speed can receive at mobile phone and form the mess code interference in the message signals, mobile phone can not detect the normal microwave signal data of sending from the base station, mobile phone can not be set up with the base station connect, reach the purpose that No Mobile Phones use.Mobile phone shows as phenomenons such as search network, no signal, no service system.The utility model adopts microcontroller chip MCU and DDS high speed signal to produce the low frequency signal source that is used for the signal interference, add the high frequency mixing of peripheral radio-frequency module simultaneously and reach the mobile phone of standard and the signal of communication of base station, interference handset is to the decoding of base station signal, thereby the transmitting power of controlling interference source equipment is simultaneously again controlled interference range to avoid the influence to base station signal or other electronic equipments.DDS (Direct Digital Synthesis, Direct Digital is synthetic) is the method that a kind of Applied Digital technology produces signal waveform.The DDS technology is based upon on the basis of sampling thheorem, and the signal waveform that it at first produces needs is sampled and quantized, and deposits memory then in as the tables of data of waiting to produce signal waveform.During signal output waveform, circuit under the control of a high stable clock signal from tables of data read output signal waveform data successively, produce digitized signal, this signal converts required analog signal waveform to by DAC again.DDS has super wide relative broadband, the prompt variable Rate of superelevation, and the ultra-fine resolution and the continuity of phase place, total digitalization able to programme, and can conveniently realize superior functions such as various modulation.

According to above-mentioned principle, the utility model discloses the mobile phone signal interference shielding device that a kind of DDS realizes, comprise before the system and level after the system, it is characterized in that: described system prime drives the output of DDS low frequency signal by MCU, the DDS low frequency output signal that produces can be sent through two passages, one the tunnel is directly through the coupler coupling, then through final stage amplifier tube amplification output; Another road is by radio-frequency (RF) switch, by the high-speed radio-frequency switch this signal is switched at random producing the signal of change at random, and then exports via the final stage amplifier tube; The signal of output is admitted to level after the system, and level mainly is that the DDS signal that prime produces is coupled to high frequency 930～960MHZ after the described system, adjusts this signal strength signal intensity by the controllable PA of one-level then.

Discuss with 4 road shielded signals below, as shown in Figure 1, system controls 4 road DDS signals by MCU, produce our needed stack frequency, and 4 the road signal will be sent to the radio frequency frequency mixing module by dual mode, wherein a kind of is to adopt MCU to control 4 road DDS signals to produce swept-frequency signal, the scanning initial frequency, stop frequency, the equal may command of speed and stepping; For a kind of mode is that MCU controls the output of 4 road DDS signals generation constant signal, constantly cut off the signal that is constantly changed by terminal radio-frequency (RF) signal switch in addition.And then export via the final stage amplifier tube.Next the DDS signal that process system prime produces is admitted to level after the system, and level mainly is that the DDS signal that prime produces is coupled to high frequency 930-960MHZ after the system, adjusts interference signal intensity by the controllable PA of one-level then; The controllable PA of described one-level is driven by MCU.In the test process of reality, the interference effect of EVAC (Evacuation Network Computer Model) and the stepping of frequency sweep, speed etc. have relation.

Claims

1, a kind of mobile phone signal interference shielding device of DDS realization, comprise before the system and level after the system, it is characterized in that: described system prime drives the output of DDS low frequency signal by MCU, the DDS low frequency output signal that produces can be sent through two passages, one the tunnel is directly through the coupler coupling, then through final stage amplifier tube amplification output; Another road is by radio-frequency (RF) switch, by the high-speed radio-frequency switch this signal is switched at random producing the signal of change at random, and then exports via the final stage amplifier tube; The signal of output is admitted to level after the system, and level mainly is that the DDS signal that prime produces is coupled to high frequency 930～960MHZ after the described system, adjusts this signal strength signal intensity by the controllable PA of one-level then.

2, the mobile phone signal interference shielding device of DDS realization according to claim 1, it is characterized in that: the DDS low frequency output signal width that described system prime produces is 200KHZ, described signal can have multichannel, the initial frequency of each road scanning, stop frequency, stepping and sweep speed all independently can be established.

3, the mobile phone signal interference shielding device of DDS realization according to claim 1, it is characterized in that: the controllable PA of described one-level is driven by MCU.