Radio frequency incoming call remote answering system based on signal relay

Abstract

The invention discloses a radio frequency incoming call remote answering system based on signal relay, comprising: an incoming call detection module for performing time domain analysis on a mobile phone emission signal through a radio frequency technology in a shielding box, and judging whether an incoming call exists in combination with a high-frequency boundary filtering and burst packet statistical mode; the signal bridging module is used for transmitting the incoming call information to the relay communication module through a digital interface; a relay communication module; a virtual call terminal; a channel encryption mechanism; the power supply management system has a low-power-consumption wake-up mechanism and long-time endurance support, and is suitable for an outdoor environment or a high-safety place; the method has the advantages that communication safety is guaranteed, remote answering is achieved, and a mobile phone is prevented from being exposed; the system can be expanded to be used for military police, government, anti-monitoring and other high-security demand scenes; a user does not need to carry a main mobile phone, and convenience and privacy are enhanced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of communication security and radio frequency relay technology, in particular to a radio frequency incoming call remote listening system based on signal relay. BACKGROUND

[0002] In recent years, with the rapid development of electronic technology, various digital products with recording function emerge in an endless stream; criminals use various eavesdropping devices for eavesdropping, and these eavesdropping devices are extremely concealed and difficult to prevent; it is just because of the emergence of these digital products with recording function and special eavesdropping equipment that enterprises, government departments and even individuals will encounter malicious eavesdropping and recording problems, which seriously infringes on the personal privacy of people and the confidentiality of enterprises and government departments; the common anti-eavesdropping method is mainly to restrict the carrying of eavesdropping devices, but since most of the current mobile phones and other portable digital products have recording function, at the same time, special eavesdropping equipment is extremely concealed and difficult to be detected, therefore, this anti-eavesdropping method of restricting the carrying of eavesdropping devices cannot effectively prevent eavesdropping.

[0003] The shielding box is a closed shell made of conductive or magnetic material, which isolates the mutual interference of internal and external electromagnetic signals through electromagnetic shielding principle, so as to protect the equipment or signal from the influence of external electromagnetic environment, and prevent internal electromagnetic radiation leakage; when the user is located in a sensitive place and it is inconvenient to carry a real mobile phone, the mobile phone needs to be placed in the shielding box to avoid positioning, but there is still a communication demand, and the existing technology cannot meet the use demand of people. SUMMARY

[0004] In order to solve the above technical problems, the present application provides a radio frequency incoming call remote listening system based on signal relay, which comprises:

[0005] The incoming call detection module performs time domain analysis on the mobile phone transmission signal in the shielding box through radio frequency technology, and judges whether there is an incoming call by combining high-frequency boundary filtering and burst packet statistical method;

[0006] The signal bridging module: transmits the incoming call information to the relay communication module through the digital interface;

[0007] The relay communication module: supports multiple wireless communication modes, and automatically selects the optimal relay link according to the distance and power consumption;

[0008] Virtual call terminal: through software simulation of SIP call process, a voice channel is established at the external listening end to realize remote listening within a range of 500-1000 meters;

[0009] Channel encryption mechanism: using encryption algorithm to encrypt voice data to ensure that information is not eavesdropped or positioned and tracked;

[0010] Power management system: with low-power wake-up mechanism and long-time endurance support, suitable for outdoor environment or high-security places.

[0011] Further supplement to the technical solution, the digital interface is SPI / UART.

[0012] Further supplement to the technical solution, the multiple wireless communication modes are WiFi Mesh, LoRa or private protocol.

[0013] Further supplement to the technical solution, the external listening end is a smart bracelet, Bluetooth headset or customized terminal.

[0014] Further supplement to the technical solution, the encryption algorithm is symmetric encryption or lightweight PQC algorithm.

[0015] Further supplement to the technical solution, the symmetric encryption algorithm is AES128.

[0016] Further supplement to the technical solution, the radio frequency technology is a combination of radio frequency detection antenna and radio frequency identification circuit or a combination of DTMF transceiver technology and wireless radio frequency technology.

[0017] Its beneficial effects are to ensure communication security while realizing remote listening, avoid exposing the location of the mobile phone, and the system can be expanded for high-security demand scenarios such as police, government, anti-monitoring, etc. Users do not need to carry the main mobile phone, enhancing convenience and privacy. DETAILED DESCRIPTION

[0018] In order to make the technical personnel in the art more clearly understand the technical solution, the technical solution of the present application will be described in detail below:

[0019] A radio frequency incoming call remote listening system based on signal relay, comprising:

[0020] Incoming call detection module: time domain analysis of mobile phone transmission signals in the shielding box through radio frequency technology, combined with high-frequency boundary filtering and burst packet statistical method to determine whether there is an incoming call;

[0021] Signal bridging module: transmit incoming call information to the relay communication module through the digital interface; the digital interface is SPI / UART.

[0022] Relay communication module: supports multiple wireless communication modes, automatically selects the optimal relay link according to distance and power consumption; multiple wireless communication modes are WiFi Mesh, LoRa or private protocol.

[0023] Virtual call terminal: simulates SIP call process through software to establish a voice channel on the external listening end, realizing remote listening within a range of 500-1000 meters;

[0024] Channel encryption mechanism: encrypt voice data using encryption algorithms to ensure that information is not eavesdropped or tracked;

[0025] Power management system: with low-power wake-up mechanism and long-time support, suitable for outdoor environment or high-security places.

[0026] Among them, the external answering end is a smart bracelet, a smart watch, a Bluetooth headset or a customized terminal.

[0027] Further, the encryption algorithm is a symmetric encryption or lightweight PQC algorithm, and the symmetric encryption algorithm is AES128.

[0028] Among them, the radio frequency technology is the combination of radio frequency detection antenna and radio frequency identification circuit or the combination of DTMF transceiver technology and wireless radio frequency technology.

[0029] The role of the combination of radio frequency detection antenna and identification circuit

[0030] Radio frequency detection antenna: responsible for receiving the radio frequency signal (such as GSM, 4G, 5G frequency band electromagnetic wave) transmitted by the mobile phone, which needs to be matched with the mobile phone communication frequency band (such as 900MHz, 1800MHz, 2.4GHz, etc.), to ensure effective coupling of the signal.

[0031] Radio frequency identification circuit: amplifies, converts (down-converts to intermediate frequency or baseband) and analog-to-digital converts (ADC) the signals received by the antenna, converts the analog radio frequency signals to digital signals for subsequent processing.

[0032] The core goal of time domain analysis: time domain analysis focuses on the characteristics of signals in the time dimension, for example: the signaling interaction between the mobile phone and the base station when the call comes in will produce a burst of pulse signals (such as paging response, channel establishment signaling), which is manifested as a sudden change in intensity or a specific pulse sequence in the time domain waveform.

[0033] By capturing the rising edge time, pulse width, amplitude change rate and other parameters of the signal, it can distinguish between regular background noise and call-related signals.

[0034] Two, the coordination mechanism of high-frequency boundary filtering and burst packet statistics

[0035] (1) High-frequency boundary filtering: eliminate interference and strengthen characteristic signals; filtering principle:

[0036] Use a band-pass filter or a high-order digital filter to set the cutoff frequency (such as higher than 500MHz), only keep the high-frequency signals of the mobile phone communication frequency band, and filter out low-frequency noise (such as power frequency interference) and non-communication frequency band radio frequency interference (such as Wi-Fi, Bluetooth signals can be further screened by frequency band division).

[0037] Typical application scenario: for example, when a GSM mobile phone rings, it will send a burst of TDMA frame signals at 900MHz frequency band, and after filtering, the time domain pulse characteristics of the frequency band can be highlighted.

[0038] (2) Burst packet statistics: quantifying signaling characteristics and establishing a judgment model;

[0039] Data packet feature extraction: when a mobile phone rings, the signaling interaction between the base station and the mobile phone (such as paging messages and SETUP instructions) is transmitted in the form of data packets, which is characterized by:

[0040] Burst frequency: multiple consecutive data packets appear within a short period of time (such as 100ms);

[0041] Packet length distribution: signaling packets are usually of fixed length (such as GSM Burst frame length of about 156.25 bits);

[0042] Time interval: the interval between packets conforms to the communication protocol specification (such as the subframe interval of 1ms in LTE).

[0043] For example, based on the implementation mode of DTMF transceiving technology and wireless radio frequency technology: when a phone call is made, the telephone switch sends a ring signal, which is converted by a high-voltage stabilizing diode and an optoelectronic coupler to output a standard square wave to the interrupt counter input of the single-chip microcomputer, completing the ringing tone detection and counting. After the single-chip microcomputer detects the ringing, it controls the relay switch to connect a resistance of about 300Ω to both ends of the telephone line, simulating the action of picking up the phone. Then, the dual-tone multi-frequency encoding and decoding chip decodes the DTMF signal input by the user to identify the user's instructions. The single-chip microcomputer then sends the instructions to the wireless transmitter through the encoding chip in the form of a radio frequency signal, and the remote receiving device receives the radio frequency signal and performs corresponding operations to achieve remote listening.

[0044] The above technical solutions only represent the preferred technical solutions of the technical solutions of the present application, and some changes that the person skilled in the art can make to some parts of them all embody the principles of the present application and are within the protection scope of the present application.

Claims

1. A radio frequency call remote listening system based on signal relay, characterized in that, The application comprises: An incoming call detection module that performs time domain analysis on mobile phone transmission signals inside the shielding box through radio frequency technology, and judges whether there is an incoming call by combining high-frequency boundary filtering and burst packet statistics; A signal bridging module that transmits incoming call information to the relay communication module through a digital interface; A relay communication module that supports multiple wireless communication modes and automatically selects the optimal relay link according to distance and power consumption; A virtual call terminal that simulates SIP call processes through software to establish a voice channel at an external receiving end, realizing remote reception within a range of 500-1000 meters; A channel encryption mechanism that uses encryption algorithms to encrypt voice data, ensuring that information cannot be eavesdropped or tracked; A power management system that has a low-power wake-up mechanism and long-time support, suitable for outdoor environments or high-security places.

2. The radio frequency call remote listening system based on signal relay according to claim 1, characterized in that, The digital interface is SPI / UART.

3. The radio frequency call remote listening system based on signal relay according to claim 1, characterized in that, The multiple wireless communication modes are WiFi Mesh, LoRa, or a private protocol.

4. The radio frequency call remote listening system based on signal relay according to claim 1, characterized in that, The external receiving end is a smart bracelet, Bluetooth headset, or customized terminal.

5. The radio frequency call remote listening system based on signal relay according to claim 1, characterized in that, The encryption algorithm is a symmetric encryption or lightweight PQC algorithm.

6. A radio frequency call remote listening system based on signal relay according to claim 5, characterized in that, The symmetric encryption algorithm is AES128.

7. The radio frequency call remote listening system based on signal relay according to claim 1, characterized in that, The radio frequency technology is a combination of radio frequency detection antennas and radio frequency identification circuits, or a combination of DTMF transceiver technology and wireless radio frequency technology.