There are several things which are place in a BTS room. And function of this component depends on various parameters like temperature, power level, humidity, etc.
A base transceiver station (BTS) is a piece of equipment that facilitates wireless communication between user equipment (UE) and a network. UEs are devices like mobile phones (handsets), WLL phones, and computers with wireless Internet connectivity. The network can be that of any of the wireless communication technologies like GSM, CDMA, wireless local loop, Wi-Fi, WiMAX or other wide area network (WAN) technology.
BTS is also referred to as the radio base station (RBS), node B (in 3G Networks) or, simply, the base station (BS). For discussion of the LTE standard the abbreviation eNB for evolved node B is widely used.
Though the term BTS can be applicable to any of the wireless communication standards, it is generally associated with mobile communication technologies like GSM and CDMA. In this regard, a BTS forms part of the base station subsystem (BSS) developments for system management. It may also have equipment for encrypting and decrypting communications, spectrum filtering tools (band pass filters), and etc. antennas may also be considered as components of BTS in general sense as they facilitate the functioning of BTS.
Typically a BTS will have several transceivers (TRXs) which allow it to serve several different frequencies and different sectors of the cell (in the case of sectorised base stations).
A BTS is controlled by a parent base station controller via the base station control function (BCF). The BCF is implemented as a discrete unit or even incorporated in a TRX in compact base stations. The BCF provides an operations and maintenance (O&M) connection to the network management system (NMS), and manages operational states of each TRX, as well as software handling and alarm collection.
The basic structure and functions of the BTS remains the same regardless of the wireless technologies.
1.1 BASE TRANSCEIVER STATION PARTS
The base transceiver station, or BTS contain the equipment for transmitting and receiving signal, antennas with base station controller (BTS).
A BTS in general following parts:
(1) Transceiver (TRX):
Quite widely referred to as the driver receiver (DRX).DRX are either in the form of single (sTRU) or a composite double radio unit (DRU).It basically dose transmission and reception of signals. It also dose sending and reception of signals to and from higher network entities (like the BSC in mobile telephony).
(2) Power amplifier (PA):
Amplifies the signal from DRX for transmission through antenna, may be integrated with DRX.
(3) Combiner:
Combines feeds from several DRXs so that they could be sent out through a single antenna. It allows for a reduction in the number of antenna used.
(4) Duplexer
For separating sending and receiving signals to/from antenna. Does sending and receiving signals through the same antenna ports (cables to antenna).
(5) Antenna
This is the structure that the BTS lies underneath; it can be installed as it is or disguised in some way (Concealed cell sites).
(6) Alarm extension system
Collects working status alarms of various units in the BTS and extends them to operations and maintenance (O&M) monitoring stations.
(7) Control function
Controls and manages the various units of BTS, including any software. On-the-spot configurations, status changes, software upgrades, etc. are done through the control function.
(8) Baseband receiver unit (BBxx)
Frequency hopping, signal DSP.
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These things are placed in a room called BTS room:
Figure 1 : BTS ROOM
So the monitoring and sensing parameters required in this BTS room are:
Temperature monitoring
Humidity monitoring
Battery level monitoring
Smoke detector
Door sensor
Light on/off
Air conditioner on/off
Camera on/off
Below is a snapshot of this monitoring and detection parameters:
Figure 2 : OVERVIEWS OF SYSTEM
I know that it’s required to run BTS (Base Transceiver System) 24×7. Thus it’s mandatory to keep monitoring all above parameters of the BTS room. But, I displayed value of temperature, humidity level on LCD as well as sent to my mobile. And I also detected door open/close, smoke detection.
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CHAPTER 2. WORKING OF BTS PARAMETER MONITORING
Figure 3 : BLOCK DIAGRAM OF PARAMETER MONITORING SYSTEM
In this project I have used LM35 temperature sensor and HR201 humidity sensor. This is a major sub-part of our project. I need to sense the temperature and humidity level continuously and display it on LCD. The LM35 is an integrated circuit sensor that can be used to measure temperature with an electrical output proportional to the temperature (in ??C).
What I need now is to give the output of LM35 and HR201 to ADC0808 pin and then it to At89s52. Measurement of the temperature and humidity level is being done using ADC and At89s52.These data is continuously display on 16×2 LCD. Then, if the temperature value is going beyond 33??C at that time controller give command to gsm module to send sms to my mobile.
I had also used LPG gas sensor MQ-6 and obstacle sensor for protection purpose. If anyone opens the door and smoke or lpg in the bts room at that time gsm sends the message to my mobile.
Figure 4 : CIRCUIT DIAGRAM
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CHAPTER 3. LITERATURE SURVEY
3.1 TEMPERATURE MONITORING SYSTEM
Authors: Mohd azizul ghafur bin rahimi
Year of publication: Faculty of Electrical & Electronics Engineering University
Malaysia Pahang. November, 2008
Conclusion:
As per constrains my project was bounded beneath but after studying this journal I can implement lcd with controller easily and get the temperature output in 16*2 display.
3.2 GSM BASED REMOTE CONTROL SYSTEM
Authors: http://hyattractions.wordpress.com
Conclusion:
Designing and implementation of a multichannel telephone based remote control system was of a truth a fascinating task to undergo .The climax of the whole process was to see that the hardware and software implementation are working as desired after several process of trial and adjustment.
This project has given us a great deal of insight into the field of communication and control engineering .The theories of communication which we have being learning from our third year was made more practicable .The ability to be able to effect control over your systems (electrical appliances, laboratory equipment, house hold appliance etc.) from far distance and in some cases from another country is of immense importance in control engineering regarding your field or your Level of education.
Besides the issue of control, the basics of communication (i.e. Global system of Mobile Communication (GSM) was made more clearer because the processes the call goes through from the dialing of the number using the 4??4 standard key to the processes of decoding the number by the Dual Tone Multi-frequency Decoder (DTMF) was also made very clear. Also the use of the F.Bus and F.Bus in cell phones and their uses in communication as the tool or medium through which our phones can communicate with other devices such as the computers, Liquid Crystal Display (LCD) screen etc.
After studying this journal I can interface gsm with controller and monitor the temperature using the gsm modem.
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CHAPTER 4. PROJECT DESCRIPTION
4.1 CIRCUIT COMPONENT
SR No.
Component description
1 Microcontroller(At89s52)
2 Temperature sensor(LM35)
3 Humidity sensor(HR201)
4 Obstacle sensor
5 Gas sensor(MQ-6)
6 16×2 LCD(JHD162)
7 GSM Module(SIM300)
8 Adapter(12V)
9 ADC(0808)
10 Transistor
11 Connectors
4.2 SOFTWARE USED
‘ Keil ??Vision:-
??Vision is a window-based software development platform that combines a robust and modern editor with a project manager and make facility tool. It integrates all the tools needed to develop embedded applications including a C/C++ compiler, macro assembler, linker/locator, and a HEX file generator. ??Vision helps expedite the development process of embedded applications by providing the following:
‘ Full-featured source code editor.
‘ Device Database?? for configuring the development tool.
‘ Project Manager for creating and maintaining our projects.
‘ Integrated Make Utility functionality for assembling, compiling, and linking our embedded applications.
‘ Dialogs for all development environment settings.
‘ True integrated source-level and assembler-level Debugger with high-speed CPU and peripheral Simulator.
‘ Advanced GDI interface for software debugging on target hardware and for connecting to a Keil’ ULINK?? Debug Adapter.
‘ Flash programming utility for downloading the application program into Flash ROM.
The ??Vision IDE and Debugger is the central part of the Keil development toolchain and has numerous features that help the programmer to develop embedded applications quickly and successfully. The Keil tools are easy to use, and are guaranteed to help us to achieve our design goals in a timely manner.
??Vision offers a Build Mode for creating applications and a Debug Mode for debugging applications. Applications can be debugged with the integrated ??Vision Simulator or directly on hardware, for example with adapters of the Keil ULINK USB-JTAG family. Developers can also use other AGDI adapters or external third-party tools for analyzing applications.
4.2.1 CREATING OWN APPLICATION IN ??VISION
To create a new project in ??Vision, we must:
‘ Select Project – New Project.
‘ Select a directory and enter the name of the project file.
‘ Select Project – Select Device and select an 8051, 251, or C16x/ST10 device
from the Device Database
‘ Create source files to add to the project.
‘ Select Project – Targets, Groups, and Files. Add/Files, select Source Group1, and add the source files to the project.
‘ Select Project – Options and set the tool options. Note when we select the target device from the Device Database’ all-special options are set automatically. We typically only need to configure the memory map of our target hardware.
4.2.2 KEIL SOFTWARE PROGRAMING PROCEDURE
How to write embedded C program in Keil Software?
Following steps are to be followed in order to develop, code and test the equipment with software.
‘ Procedure Steps
Step-1:
Install KEIL uVision in your PC, Then after Click on that ‘KEIL ??Vision’ icon. After opening the window go to toolbar and select Project Tab then close previous project.
Step-2:
Next select New Project from Project Tab.
Step-3:
Then it will open ‘Create New Project’ window. Select the path where you want to save project and edit project name.
Step-4:
Next it opens ‘Select Device for Target’ window, it shows list of companies and here you can select the device manufacturer company.
Step-5:
For an example, for your project purpose you can select the chip as 89c51/52 from Atmel Group. Next Click OK Button, it appears empty window here you can observe left side a small window i.e., ‘Project Window’. Next create a new file.
Step-6:
From the Main tool bar Menu select ‘File’ Tab and go to New, then it will open a window, there you can edit the program.
Step-7:
Here you can edit the program as which language will you prefer either Assembly or
C.
Step-8:
After editing the program save the file with extension as ‘.c’ or ‘.asm’, if you write a program in Assembly Language save as ‘.asm’ or if you write a program in C Language save as ‘.c’ in the selected path. Take an example and save the file as ‘test.c’.
Step-9:
Then after saving the file, compile the program. For compilation go to project window select ‘source group’ and right click on that and go to ‘Add files to Group’.
Step-10:
Here it will ask which file has to Add. For an example here you can add ‘test.c’ as you saved before.
Step-11:
After adding the file, again go to Project Window and right click on your ‘c file’ then select ‘Build target’ for compilation. If there is any ‘Errors or Warnings’ in your program you can check in ‘Output Window’ that is shown bottom of the Keil window.
Step-12:
Here in this step you can observe the output window for ‘errors and warnings’.
Step-13:
If you make any mistake in your program you can check in this slide for which error and where the error is by clicking on that error.
Step-14:
After compilation then next go to Debug Session. In Tool Bar menu go to ‘Debug’ tab and select ‘Start/Stop Debug Session’.
Step-15:
Here a simple program for ‘LED’s Blinking’. LEDS are connected to PORT-1. You can observe the output in that port.
Step-16:
To see the Ports and other Peripheral Features go to main toolbar menu and select peripherals.
Step-17:
In this slide see the selected port i.e., PORT-1.
Step-18:
Start to trace the program in sequence manner i.e., step by step execution and observe the output in port window.
Step-19:
After completion of Debug Session Create a Hex file for Burning the Processor. Here to create a Hex file go to project window and right click on Target next select ‘Option for Target’.
Step-20:
It appears one window; here in ‘target tab’ modify the crystal frequency as you connected to your microcontroller.
Step-21:
Next go to ‘Output’ tab. In that Output tab click on ‘Create HEX File’ and then click OK.
Step-22:
Finally Once again compile your program. The Created Hex File will appear in your path folder.
4.2.3 APPLICATIONS OF KEIL SOFTWARE
Select Project – Rebuild all target files or Build target.
‘ Debugging an Application in ??Vision:
To debug an application created using ??Vision,
We must:
‘ Select Debug – Start/Stop Debug Session.
‘ Use the Step toolbar buttons to single-step through your program. We may enter G, main in the Output Window to execute to the main C function.
‘ Open the Serial Window using the Serial #1 button on the toolbar.
‘ Debug your program using standard options like Step, Go, Break, and so on.
4.3 INTERFACING DONE:
‘ Microcontroller with sensors
‘ LCD
‘ ADC0808
‘ GSM Sim 300
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CHAPTER 5. MICROCONTROLLER AT89S52
5.1 DESCRIPTION OF AT89S52
This is the heart or main part of my project. It controls the all parameters in my project. It is also control the gsm sim 300 module.
It’s quite typical part to choose a microcontroller that has requisite skills! As I am familiar with 8051 and Phillips ICs at initial stage, I need somewhat analytical approach to think for the best. Though I am given At89s52, I compared it with others to know more.
The AT89S52 is a low-power, high-performance CMOS 8-bit microcontroller with 8K bytes of in-system programmable Flash memory. The device is manufactured using Atmel’s high-density non-volatile memory technology and is compatible with the industry standard 80C51 instruction set and pinout. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional non-volatile memory programmer.
By combining a versatile 8-bit CPU with in-system programmable flash on a monolithic chip, the Atmel AT89S52 is a powerful microcontroller which provides a highly-flexible and cost-effective solution to many embedded control applications.
The AT89S52 provides the following standard features: 8K bytes of flash, 256 bytes of RAM, 32 I/O lines, Watchdog timer, two data pointers, three 16-bit timer/counters, axis-vector two-level interrupt architecture, a full duplex serial port, on-chip oscillator, and clock circuitry. In addition, the AT89S52 is designed with static logic for operation down to zero frequency and supports two software selectable power saving modes.
The Idle Mode stops the CPU while allowing the RAM, timer/counters, serial port, and interrupt system to continue functioning. The Power-down mode saves the RAM contents but freezes the oscillator, disabling all other chip functions until the next interrupt or hardware reset.
FEATURE of At89s52:
‘ High-performance, Low-power Atmel?? AVR?? 8-bit Microcontroller
‘ 8K Bytes of In-System Programmable (ISP) Flash Memory
‘ 4.0V to 5.5V Operating Range
‘ Fully Static Operation: 0 Hz to 33 MHz
‘ Three-level Program Memory Lock
‘ 256 x 8-bit Internal RAM
‘ 32 Programmable I/O Lines
‘ Three 16-bit Timer/Counters
‘ Eight Interrupt Sources
‘ Full Duplex UART Serial Channel
‘ Low-power Idle and Power-down Modes
‘ Interrupt Recovery from Power-down Mode
‘ Watchdog Timer
‘ Dual Data Pointer
‘ Power-off Flag
‘ Fast Programming Time
‘ Flexible ISP Programming (Byte and Page Mode)
‘ Green (Pb/Halide-free) Packaging Option
Figure 5 : PIN CONFIGURATION
5.1 PIN DESCRIPTION OF AT89S52
(1) VCC: – Supply voltage.
(2) VSS: – Ground.
(3) PORT 0:-
Port 0 is an 8-bit open drain bidirectional I/O port. As an output port, each pin can sink eight TTL inputs. When 1s are written to port 0 pins, the pins can be used as high-impedance inputs.
Port 0 can also be configured to be the multiplexed low-order address/data bus during accesses to external program and data memory. In this mode, P0 has internal pull-ups.
Port 0 also receives the code bytes during Flash programming and outputs the code bytes during program verification. External pull-ups are required during program verification.
(4) PORT 1:-
Port 1 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 1 output buffers can sink/source four TTL inputs. When 1s are written to Port 1 pins, they are pulled high by the internal pull-ups and can be used as inputs. As inputs, Port 1 pins that are externally being pulled low will source current (IIL) because of the internal pull-ups. In addition, P1.0 and P1.1 can be configured to be the timer/counter 2 external count input (P1.0/T2) and the timer/counter 2 trigger input (P1.1/T2EX), respectively, as shown in the following table.
Table 1 : PORT 1 OF AT89S52
Port 1 also receives the low-order address bytes during Flash programming and verification.
(5) PORT 2:-
Port 2 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 2 output buffers can sink/source four TTL inputs. When 1s are written to Port 2 pins, they are pulled high by the internal pull-ups and can be used as inputs. As inputs, Port 2 pins that are externally being pulled low will source current (IIL) because of the internal pull-ups.
Port 2 emits the high-order address byte during fetches from external program memory and during accesses to external data memory that uses 16-bit addresses (MOVX @ DPTR). In this application, Port 2 uses strong internal pull-ups when emitting 1s. During accesses to external data memory that uses 8-bit addresses (MOVX @ RI), Port 2 emits the contents of the P2 Special Function Register.
Port 2 also receives the high-order address bits and some control signals during Flash programming and verification.
(6) PORT 3:-
Port 3 is an 8-bit bidirectional I/O port with internal pull-ups. The Port 3 output buffers can sink/source four TTL inputs. When 1s are written to Port 3 pins, they are pulled high by the internal pull-ups and can be used as inputs. As inputs, Port 3 pins that are externally being pulled low will source current (IIL) because of the pull-ups.
Port 3 receives some control signals for Flash programming and verification.
Port 3 also serves the functions of various special features of the AT89S52, as shown in the following table.
Table 2 : PORT 3 OF AT89S52
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(7) RST:-
Reset input. A high on this pin for two machine cycles while the oscillator is running resets the device. This pin drives high for 98 oscillator periods after the Watchdog times out. The DISRTO bit in SFR AUXR (address 8EH) can be used to disable this feature. In the default state of bit DISRTO, the RESET HIGH out feature is enabled.
(8) ALE/PROG:-
Address Latch Enable (ALE) is an output pulse for latching the low byte of the address during accesses to external memory. This pin is also the program pulse input (PROG) during Flash programming.
In normal operation, ALE is emitted at a constant rate of 1/6 the oscillator frequency and may be used for external timing or clocking purposes. Note, however, that one ALE pulse is skipped during each access to external data memory.
If desired, ALE operation can be disabled by setting bit 0 of SFR location 8EH. With the bit set, ALE is active only during a MOVX or MOVC instruction. Otherwise, the pin is weakly pulled high. Setting the ALE-disable bit has no effect if the microcontroller is in external execution mode.
(9) PSEN:-
Program Store Enable (PSEN) is the read strobe to external program memory.
When the AT89S52 is executing code from external program memory, PSEN is activated twice each machine cycle, except that two PSEN activations are skipped during each access to external data memory.
(10) EA/VPP:-
External Access Enable. EA must be strapped to GND in order to enable the device to fetch code from external program memory locations starting at 0000H up to FFFFH. Note, however, that if lock bit 1 is programmed, EA will be internally latched on reset.
EA should be strapped to VCC for internal program executions.
This pin also receives the 12-volt programming enable voltage (VPP) during Flash programming.
(11) XTAL1:-
Input to the inverting oscillator amplifier and input to the internal clock operating circuit.
(12) XTAL2:-
Output from the inverting oscillator amplifier.
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CHAPTER 6. HARDWARE TOOLS AND ITS INTERFACING
WITH AT89S52
6.1 16*2 LCD DISPLAY
A liquid crystal display (LCD) is a flat panel display, electronic visual display, or video display that uses the light modulating properties of liquid crystals (LCs). LCs do not emit light directly.
LCDs are used in a wide range of applications, including computer monitors, television, instrument panels, aircraft cockpit displays, signage, etc. They are common in consumer devices such as video players, gaming devices, clocks, watches, calculators, and telephones. LCDs have replaced cathode ray tube (CRT) displays in most applications. They are available in a wider range of screen sizes than CRT and plasma displays, and since they do not use phosphors, they cannot suffer image burn-in. LCDs are, however, susceptible to image persistence.
LCDs are more energy efficient and offer safer disposal than CRTs. Its low electrical power consumption enables it to be used in battery- powered electronic equipment. It is an electronically modulated optical device made up of any number of segments filled with liquid crystals and arrayed in front of a light source (backlight) or reflector to produce images in colour or monochrome. The most flexible ones use an array of small pixels. The earliest discovery leading to the development of LCD technology, the discovery of liquid crystals, dates from 1888. By 2008, worldwide sales of televisions with LCD screens had surpassed the sale of CRT units. Following figure is a 16×2 LCD.
Monochrome passive-matrix LCDs were standard in most early laptops (although a few used plasma displays) and the original Nintendo Game Boyuntil the mid-1990s, when colour active-matrix became standard on all laptops. The commercially unsuccessful Macintosh Portable (released in 1989) was one of the first to use an active-matrix display (though still monochrome).
Passive-matrix LCDs are still used today for applications less demanding than laptops and TVs. In particular, portable devices with less information content to be displayed, where lowest power consumption (no backlight), low cost and/or readability in direct sunlight are needed, use this type of display.
Figure 6 : 16×2 LCD
Table 3 : LCD PIN DESCRIPTION
‘ FEATURE OF LCD:
‘ LCD is finding widespread use replacing LEDs.
‘ The declining prices of LCD.
‘ The ability to display numbers, characters, and graphics.
‘ Built-in controller.
‘ Incorporation of a refreshing controller into the LCD, thereby relieving the
‘ CPU for the task of refreshing the LCD.
‘ Ease of programming for characters and graphics.
Table 2: BASIC COMMANDS TO OPERATE LCD
‘ Advantages and Disadvantages of LCD
In spite of LCDs being a well proven and still viable technology, as display devices LCDs are not perfect for all applications.
‘ Advantages:-
‘ Very compact and light.
‘ Low power consumption.
‘ No geometric distortion.
‘ Little or no flicker depending on backlight technology.
‘ Not affected by screen burn-in.
‘ Can be made in almost any size or shape.
‘ No theoretical resolution limit.
‘ Disadvantages:-
‘ Limited viewing angle, causing colour, saturation, contrast and brightness to vary, even within the intended viewing angle, by variations in posture.
‘ Bleeding and uneven backlighting in some monitors, causing brightness distortion, especially toward the edges.
‘ Smearing and ghosting artifacts caused by slow response times (>8 ms) and "sample and hold" operation.
‘ Fixed bit depth, many cheaper LCDs are only able to display 262,000 colours. 8-bit S-IPS panels can display 16 million colours and have significantly better black level, but are expensive and have slower response time.
‘ Low bit depth results in images with unnatural or excessive contrast.
‘ Input lag
‘ Dead or stuck pixels may occur during manufacturing or through use.
‘
6.2 TEMPERATURE SENSOR LM35
This is a major sub-part of my project. I need to sense the temperature continuously and display it on LCD.
The LM35 is an integrated circuit sensor that can be used to measure temperature with an electrical output proportional to the temperature (in ??C).
Figure 7 : LM35
FUNCTION OF LM35:
It has an output voltage that is proportional to the Celsius temperature.
FEATURE OF LM35:
‘ Calibrated Directly in ?? Celsius (Centigrade).
‘ Linear + 10 mV/??C Scale Factor.
‘ 0.5??C Ensured Accuracy (at +25??C).
‘ Rated for Full ’55??C to +150??C Range.
‘ Suitable for Remote Applications.
‘ Low Cost Due to Wafer-Level Trimming.
‘ Operates from 4 to 30 V.
‘ Less than 60-??A Current Drain.
‘ Low Self-Heating, 0.08??C in Still Air.
‘ Nonlinearity Only ”C Typical.
‘ Low Impedance Output, 0.1 ?? for 1 mA Load.
RELATION BETWEEN TEMPERATURE AND VOLTAGE:
The general equation used to convert output voltage to temperature is:
Temperature (??C) = Vout * (100 ??C/Vcc)
Thus I now have appropriate relation between voltage and temperature. What I need now is to give the output of LM35 to ADC to At89s52. So, next I need to interface ADC and At89s52.
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6.3 ADC0808
In simple words, Analog to Digital converter is an electronic device which converts analog signal from our real world into a machine readable or binary or digital format. So I will use ADC0808.
These are some features:
‘ Easy interface to all microprocessors
‘ Operates ratio metrically or with 5 V DC or analog span adjusted voltage
Reference
‘ No zero or full-scale adjust required
‘ 8-channel multiplexer with address logic
‘ 0V to VCC input range
‘ Outputs meet TTL voltage level specifications
‘ ADC0808 equivalent to MM74C949
Figure 8 : ADC PIN DIAGRAM
6.4 HUMIDITY SENSOR HR201
This is also major sub-part of my project. I need to sense the humidity level continuously and display it on LCD.
HR201 is a new kind of humidity-sensitive resistor made from organic macromolecule materials, it can be used in occasions like: hospitals, storage, workshop, textile industry, tobaccos, pharmaceutical field, meteorology, etc.
Figure 9 : HUMIDITY SENSOR HR201
‘
Operating range humidity(20-95%RH) temperature(0-60Celsius)
Power supply 1.5V AC(Max sine)
Operating frequency 500Hz-2kHz
Rated power 0.2mW(Max sine)
Central value 23k??(at 25Celsius, 1kHz ,1V AC, 60%RH)
Impedance range 19.8-50.2k??(at 25Celsius, 1kHz ,1V AC, 60%RH)
Accuracy +-5%RH
Hysteresis +-1%RH
Long-term stability +-1%RH/year
Response time <10s
Table 4 : SPECIFICATION OF HR201
Features of humidity sensor HR201:
‘ Excellent linearity
‘ low power consumption
‘ wide measurement range
‘ quick response
‘ anti-pollution
‘ high stability
‘ high performance
‘
6.5 OBSTACLE(INFRARED) SENSOR
Obstacle Sensor is used to detect objects and obstacles in front of sensor. Sensor keeps transmitting modulated infrared light and when any object comes near, it is detected by the sensor by monitoring the reflected light from the object.
So in this project when anyone opens the door this sensor senses this and send message to my mobile using gsm module. So by using this sensor security of bts room will increase.
FEATURES OF OBSTACLE SENSOR:
‘ 1 KHz Modulated IR transmitter LEDs.
‘ Ambient light protected IR receiver.
‘ 3 pin easy interface connector.
‘ Indicator LED.
‘ Up to 10cm range for white object.
‘ Can differentiate between dark and light colours.
‘ Active Low on object detection.
SPECIFICATION OF OBSTACLE SENSOR:
‘ Power Supply : 5V DC Power Consumption: 50mA max.
‘ Detection range 10 cm.
‘ Operation range varies according to colour of the object, light colour has more range.
‘ Detection Indicator LED.
‘ Digital output. Active with logic ‘0’.
Figure 10 : OBSTACLE SENSOR
OPERATION OF OBSTACLE SENSOR:
Basic Idea is to send infrared light through IR LEDs which is then reflected by any object in front of sensor.
One of the biggest problems that can cause the malfunctioning of an IR proximity sensor is the ambient light and surrounding sources of IR like the sun and halogen lamps that can cause false triggering of the sensor due to emission of infrared light.
Figure 11 : DETECTION OF OBJECT
To avoid getting false detection the solution is to send pulses of IR light at a certain frequency instead of a constant beam, and build a receiver that would only detect IR pulses of the same exact frequency, cutting of all pulses of higher or lower frequency.
The kind of device capable of filtering signals this way is called a band pass filter. There are a lot of types of band pass filters; a whole branch of electricity is dedicated to this subject. The central frequency is fixed by the constructor usually at 1 kHz.
IR receiver filters all the source of light except the 1Khz IR signal. It all starts by generating the 1 KHz pulses of electricity that are fed to an IR LED, emitting 1 KHz pulses of Infra Red light. A weaker signal but with the same frequency is reflected from an eventual obstacle to the IR receiver, it passes through the IR-PASS filter, which will eliminate other sources of light which are not IR (visible light).
The IR-PASS filter still detects a lot of noise due to other sources of IR light like the sun for example, so the signals received by the diode are fed to another stage composed of an active filter to select the 1Khz IR signals among all others, amplify it and demodulate it, providing a clean logic output (5 or 0 volts).
‘
6.6 GAS SENSOR MQ-6
This sensor is very important for saving base transceiver room from the fire. When, this sensor senses the smoke or lpg at that time controller send message to my mobile about it by gsm module.
FEATURES OF GAS SENSOR MQ-6:
‘ High sensitivity to LPG, is-butane, propane.
‘ Sensitive to alcohol, smoke.
‘ Fast response.
‘ Stable and long life.
‘ Simple drive circuit.
Figure 12 : GAS SENSOR MQ-6
Resistance value of MQ-6 is difference to various kinds and various concentration gases. So, when using these components, sensitivity adjustment is very necessary. We recommend that calibrate the detector for 1000ppm of LPG concentration in air and use value of Load resistance ( RL) about 20K?? (10K?? to 47K??).
When accurately measuring, the proper alarm point for the gas detector should be determined after considering the temperature and humidity influence.
‘
SPECIFICATIONS OF GAS SENSOR:
Table 5 : STANDARD WORK CONDITION
Table 6 : ENVIRONMENT CONDITION
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6.7 GSM SIM 300 MODULE
This is last and main part of my project. In this project I get the value of temperature and humidity level by sms using this module. I also get message of smoke or lpg detection and door open detection of bts room.
This GSM Modem can accept any GSM network operator SIM card and act just like a mobile phone with its own unique phone number. Advantage of using this modem will be that you can use its RS232 port to communicate and develop embedded applications. Applications like SMS Control, data transfer, remote control and logging can be developed easily.
The modem can either be connected to PC serial port directly or to any microcontroller. It can be used to send and receive SMS or make/receive voice calls. It can also be used in GPRS mode to connect to internet and do many applications for data logging and control. In GPRS mode you can also connect to any remote FTP server and upload files for data logging.
This GSM modem is a highly flexible plug and play quad band GSM modem for direct and easy integration to RS232 applications. Supports features like Voice, SMS, Data/Fax, GPRS and integrated TCP/IP stack.
FEATURES OF GSM SIM 300:
‘ Highly Reliable for 24×7 operations with Matched Antenna.
‘ Status of Modem Indicated by LED.
‘ Simple to Use & Low Cost.
‘ Quad Band Modem supports all GSM operator SIM cards.
Figure 13 : GSM SIM 300 MODULE
APPLICATIONS OF GSM SIM 300:
‘ SMS based Remote Control & Alerts.
‘ Security Applications.
‘ Sensor Monitoring.
‘ GPRS Mode Remote Data Logging.
For sending SMS in text Mode:
‘ AT+CMGF=1 press enter
‘ AT+CMGS=’mobile number’ press enter
Once The AT commands is given’ >’ prompt will be displayed on the screen.
Type the message to send via SMS. After this, press ‘ctrl+Z’ to send the SMS.
If the SMS sending is successful, ‘ok’ will be displayed along with the message
Number.
For reading SMS in the text mode:
‘ AT+CMGF=1 Press enter
‘ AT+CMGR= no.
Number (no.) is the message index number stored in the sim card. For new SMS, URC will be received on the screen as +CMTI: SM ‘no’. Use this number in the AT+CMGR number to read the message.
Figure 14 : INTERFACING DONE WITH AT89S52
‘
CHAPTER 7. TROUBLESHOOTING
1) LCD:
I am getting problem of displaying character on 16×2 LCD. Then I connected Vee to Ground. So, character display got improved.
Reason for this is like this:
LCD can be considered as bunch of small LEDs.
Figure 15 : LCD INTERNAL CONFIGURATION
Thus giving it Vcc, it turns on these LEDs brighter. And giving it GND turn off the LEDs, thus the character is displayed when giving it GND.
2) ADC conversion:
In my project, all sensor giving analogue output but controller works only into digital data. So for getting digital output I had used adc0808 IC.
3) Input power supply:
In my project, I needed +12V and +5V DC voltage for input power supply for GSM module and controller. That’s why I have used DC adapter of +12V for input power supply for GSM module.
To solve the problem of making another +5V supply, I directly used 12V from adapter and diode took out +5V supply for controller.’
CHAPTER 8. CONCLUSION
This project achieved a lot of its goal. Temperature sensor LM35 and humidity sensor HR201 sense temperature and humidity then At89s52 microcontroller send this value to 16×2 display to indicate sensed temperature and Humidity level value continuously. Then controller compare the value with define value. If sense value is out of limit than it send message of value is beyond the critical value on my mobile phone through GSM module. As same as I used gas or smoke sensor and obstacle sensor. If these two sensors detect smoke or lpg and door open at that time controller send the detection to my mobile using GSM module.
This device work successfully. After completing this project I come to know many things about microcontroller, networking program as well as GSM module.
8.1 FUTURE SCOPE
The microcontroller based BTS parameter monitoring system designed in this project has a lot of advantages, but can also be improved on. There is a lot of improvement that can be made to the project that would result in a more reliable system as stated in the recommendations section.
I can extend this project to sense and monitor other BTS parameter like, fuel level, power level, battery level, Air conditioner on/off etc.
8.2 REFERENCES
1) Understanding the project: www.btsmonitoring.com
2) Datasheet of At89s52: http://www.datasheetcatalog.org/datasheet/atmel/2486S.pdf
3) Simple AVR Programmer: http://www.roboticsindia.com/showthread.php/2349-
Want-to-buy-build-serial-port-avr-programmer
4) LCD interfacing: http://www.8051projects.net/lcd-interfacing/
5) Temperature (ADC) interfacing:
http://www.robotplatform.com/knowledge/ADC/adc_tutorial_1.html