CN212211403U

CN212211403U - NB signal testing device

Info

Publication number: CN212211403U
Application number: CN202020911851.2U
Authority: CN
Inventors: 费战波; 张毅; 邬宝寅
Original assignee: SUNTRONT TECH CO LTD
Current assignee: SUNTRONT TECH CO LTD
Priority date: 2020-05-27
Filing date: 2020-05-27
Publication date: 2020-12-22
Anticipated expiration: 2030-05-27

Abstract

The utility model discloses a NB signal testing arrangement, main control unit way, NB module circuit, bluetooth communication module, SIM card switching circuit, outside SIM card interface circuit, voltage electricity survey circuit, power supply circuit, the device detectable removes, UNICOM, the three big operators' of telecommunications NB signal, guarantees that NB thing networking product NB communication is normal. The utility model discloses circuit design is compact, and the circuit low power dissipation.

Description

NB signal testing device

Technical Field

The utility model relates to a test field, specifically speaking involve a NB signal testing arrangement.

Background

With the development of society and the transformation of energy structures in China, water meters and gas meters have already gone into thousands of households, but the traditional mechanical water meters need to be manually checked, so that the problems of low efficiency, high labor cost, easy error of data recording, difficult maintenance and management, inconvenient payment and the like are inevitable.

The GPRS remote meter reading solves a series of problems of manual meter reading, is higher in efficiency, safer and more convenient for user payment, but also has the problems of smaller user capacity, high power consumption and poor signal of a communication base station. The common water-gas meter is required to be powered by a battery, so that high requirements are provided for power consumption of meters, the instantaneous maximum current of 2G communication can reach 2A generally, and great difficulty is also added to the selection of battery performance and the cost control. The NB-IoT well solves the problem faced by the GPRS meter reading scheme. The NB-IoT meter reading has the function of inheriting GPRS, and has 50-100 times of uplink capacity improvement compared with 2G/3G/4G, which means that the NB-IoT can provide 50-100 times of access number compared with the existing wireless technology under the same base station coverage range.

At present, mobile operators, communication operators and telecom have opened NB Internet of things services to cooperate with reading water and gas meter data in residents, and whether signals of NB Internet of things network cards are normal or not is the key of the whole NB meter reading system. Common NB-IoT water meters and gas meters have three networks of mobile communication telecommunication, and the signal frequency ranges are different. The conditions of field signals need to be known in the installation and debugging processes of NB-IoT water and gas meters, meter end debugging and problem finding are facilitated, and equipment capable of testing the field NB signals is lacked at present.

Disclosure of Invention

The utility model aims at providing a multifrequency section NB signal test device, the device detectable removes, UNICOM, the three big operator NB's of telecommunications signal, guarantees that NB thing networking product NB communication is normal.

In order to achieve the above object, the technical solution of the present invention is as follows:

the utility model provides a NB signal testing arrangement, contains main control unit way, NB module circuit, bluetooth communication module, SIM card switching circuit, outside SIM card interface circuit, voltage electricity and surveys circuit, power supply circuit, characterized by: the NB module circuit is used for establishing connection with an operator network, needs to access a mobile phone SIM card of the operator network, and communicates with the main controller by adopting a low-power serial port; the Bluetooth communication module is used for receiving data sent by a mobile phone and forwarding the data to the main controller, and the Bluetooth communication module and the main controller are in serial communication with each other through a low-power consumption port; the SIM card switching circuit adopts 4 one-out-of-four analog switches, divides each signal into four paths, respectively corresponds to three surface-mounted SIM cards and one external SIM card, and a selection pin of each analog switch is connected with a port of the main controller through a level matching circuit; the power circuit is powered by a 3.7V lithium battery carried by the device shell; the voltage detection circuit is used for detecting the voltage of a device power supply and introducing the ADC detection voltage of the main controller, and the voltage detection circuit power supply is controlled by a triode switch; the external SIM card interface circuit is used for connecting an external SIM card and the SIM card switching circuit.

The utility model has the advantages that:

(1) the utility model relates to a NB signal testing arrangement, the device detectable removes, UNICOM, the three big operators' of telecommunications NB signal, guarantees that NB thing networking product NB communication is normal.

(2) The utility model relates to a NB signal testing arrangement, circuit design is compact, and the circuit low power dissipation.

Drawings

Fig. 1 is the circuit schematic block diagram of an NB signal testing device of the present invention.

Detailed Description

The technical solution of the present invention will be described in detail with reference to the accompanying drawings and the detailed description

As shown in the attached drawings: the utility model provides a NB signal testing arrangement, contains main control unit way, NB module circuit, bluetooth communication module, SIM card switching circuit, outside SIM card interface circuit, voltage electricity and surveys circuit, power supply circuit, characterized by: the NB module circuit is used for establishing connection with an operator network, needs to access a mobile phone SIM card of the operator network, and communicates with the main controller by adopting a low-power serial port; the Bluetooth communication module is used for receiving data sent by a mobile phone and forwarding the data to the main controller, and the Bluetooth communication module and the main controller are in serial communication with each other through a low-power consumption port; the SIM card switching circuit adopts 4 one-out-of-four analog switches, each signal of four signal lines of the SIM card is divided into four paths which respectively correspond to three surface-mounted SIM cards and an external SIM card, and a selection pin of the analog switch is connected with a port of the main controller through a level matching circuit; the power circuit is powered by a 3.7V lithium battery carried by the device shell; the voltage detection circuit is used for detecting the voltage of a device power supply and introducing the ADC detection voltage of the main controller, and the voltage detection circuit power supply is controlled by a triode switch; the external SIM card interface circuit is used for connecting an external SIM card and the SIM card switching circuit.

NB module circuit: the NB module adopts a full-network-through module M5310-A of a Middling Internet of things (IOT) limited company, adopts a standard circuit at the periphery and adopts an MOS tube switch to supply power for the NB module.

SIM card switching circuit: the four-in-one analog switch 74HC4052 is adopted to form a card switching circuit, each 74HC4052 comprises two four-in-one analog switch units, 2 74HC4052 are adopted to share four analog switch units, multi-path selection of four signals such as VSIM, SIM _ IO, SIM _ CLK, SIM _ RST and the like is achieved, each signal is divided into four paths, and the four paths correspond to three surface-mounted SIM cards and one external SIM card respectively. The select pins S0, S1 of 74HC4052 are connected to the P3.0, P3.1 ports of the host controller through level matching circuits.

The Bluetooth communication module: by adopting a low-power-consumption Bluetooth module LSD4BT of the Lierda company, the Bluetooth module receives data and instructions sent by an external mobile phone and communicates the data and the instructions to a main controller through a serial port, a Bluetooth serial port switch control end of the Bluetooth module is connected with a P2.3 port of the main controller, a Bluetooth module reset control end is connected with a PJ.3 end of the main controller, a Bluetooth connection enable control end is connected with a PJ.1 end of the main controller, a Bluetooth module connection state control end is connected with a P2.2 end of the main controller,

the Bluetooth serial port opening mark (input port) of the Bluetooth module is connected with the PJ.2 end of the main controller, and the RXD end and the TXD end of the serial port of the Bluetooth module are respectively connected with the P3.4-P3.5 ends of the main controller.

A power supply circuit: adopt the device casing from taking 3.7V lithium cell power supply, 3.7V voltage provides operating voltage to main control unit, bluetooth module after stabilizing voltage to 3.0V through voltage stabilizing chip, and the device casing still is equipped with the knob switch, and this knob switch can regard as awakening switch, and the knob switch is a knob potentiometre really, and the one end of knob potentiometre with take a percentage be connected with host computer ADC pin. When the device is not operated for a long time, the device enters a dormant state, and the device can be awakened by rotating the knob switch.

A voltage detection circuit: the circuit is used for detecting the voltage of the battery and comprises resistors R6-R10, triodes Q1 and Q5, wherein the resistors R9 and the resistors R10 are connected in series to divide voltage, the ADC of the main controller is introduced to detect the power voltage, and the power circuit of the voltage detection circuit is controlled by the switch of the triode Q1.

External SIM card interface circuit: the SIM card switching circuit is used for connecting the external SIM card and the SIM card switching circuit.

A main controller: the main controller part comprises a single chip microcomputer model:

the working principle of the utility model is as follows: after the Bluetooth module is matched with the mobile phone, the device can realize communication between the mobile phone and the NB module, and after the device is matched with the mobile phone, the mobile phone can send instructions to control the device, including controlling the NB module to be powered on or powered off, acquiring the voltage of the device, and switching the SIM card on the periphery of the NB module. The specific process comprises the following steps:

and (3) climbing a network: the main controller receives the AT instruction sent by the mobile phone through the Bluetooth to control the NB module to log on the network.

Acquiring signal strength: the main controller receives AT instruction control and NB module communication sent by the mobile phone through the Bluetooth, acquires the signal intensity of the NB module, forwards the signal intensity to the mobile phone, and displays the signal intensity on the mobile phone.

Obtaining a communication success rate: and in the network-on state, the mobile phone sends data to the base station every 30s through the Bluetooth, the main controller and the NB module, judges whether the sending is successful according to a response frame returned by the NB module to the mobile phone, and calculates the success rate to display the success rate on the mobile phone. For example, if the handset sent 20 times in the previous ten minutes and 19 received response frames, the success rate is 95%.

Claims

1. The utility model provides a NB signal test device contains main control unit, NB module circuit, bluetooth communication module, SIM card switching circuit, outside SIM card interface circuit, voltage detection circuit, power supply circuit, characterized by: the NB module circuit is used for establishing connection with an operator network, needs to access a mobile phone SIM card of the operator network, and communicates with the main controller by adopting a low-power serial port; the Bluetooth communication module is used for receiving data sent by a mobile phone and forwarding the data to the main controller, and the Bluetooth communication module and the main controller are in serial communication with each other through a low-power consumption port; the SIM card switching circuit adopts 4 one-out-of-four analog switches, divides each signal into four paths, respectively corresponds to three surface-mounted SIM cards and one external SIM card, and a selection pin of each analog switch is connected with a port of the main controller through a level matching circuit; the power circuit is powered by a 3.7V lithium battery carried by the device shell; the voltage detection circuit is used for detecting the voltage of a device power supply and introducing the ADC detection voltage of the main controller, and the voltage detection circuit power supply is controlled by a triode switch; the external SIM card interface circuit is used for connecting an external SIM card and the SIM card switching circuit.