The main object of this project is to make a testbed for MIMO-OFDM antenna 4G technology, we are using MIMO instead of SISO (conventional systems uses one antenna at both transmitting and receiving ends) or MISO, because of its robust nature then that of the others, as it give very good QOSs( Quality Of Services) at very high data rate, this is based on the Theory of Characteristics Modes(TCM) which identify the different modes of radiations of antenna, by properly choosing the modes of radiations. The Theory of Characteristics Modes help us to obtain the radiations pattern of arbitrarily-shaped metallic structure. The radiations patterns, not only present really attractive orthogonal properties, but also bring physical insight into the radiating phenomena taking place on the antenna. For the MIMO-OFDM the first part was to make a hardware part in which we used 3 antennas at the receiving end and transmitting end both, we are using aurduino as a microprocessor , and the second part will be software. 1.1 HARDWARE PART: In the Hardware our first step was to select different components, following is the list of the components we are using in our project:· Aurduino 2560 Microprocessor· Zigbee 2530 Module· MAX 232· Digital Humidity and Temperature (DHT)· LCD 16*2· Crystal Oscillator 16MHZ· Regulator 7805· Capacitors· Resistors· Inductors· Diodes· LEDs 1.
1.1 AURDUINO 2560 MICROPROCESSOR:Arduino is an open-source electronics platform based on very simple hardware and software. Arduino circuit boards are able to read inputs light on a sensor, a finger on a button, or a Facebook message and turn it into an output activating a motor, turning on an LED, publishing something online. You can tell your board what to do by sending a set of instructions to the microcontroller on the board. To make possible all these things you use the Arduino programming language (based on connections), and the Arduino Software (IDE), based on Processing.
In our project we are using 2560 model which is very efficient and fast in processing. It is being used when we required more memory more I/O pins and more sketch memory and more RAM. The Arduino Mega 2560 is programmed using the Arduino Software (IDE), our Integrated Development Environment common to all our boards and running both online and offline. With 54 digital I/O pins, 16 analog inputs and a larger space for our sketch. This gives our projects larger room and opportunities for maintaining the effectiveness of the Arduino platform. We will see in our software phase that how to connect your Mega2560 board to the computer and upload your first sketch.1.
1.2 ZIGBEE 2530 MODULE:ZigBee is an IEEE 802.15.4 based, low power, low data rate supporting wireless networking standard, which is basically used for two-way communication between sensors and control system. It is a short-range communication standard like Bluetooth and Wi-Fi, covering range of 10 to 100 meters. The difference being while Bluetooth and Wi-Fi are high data rate communications standard supporting transfer of complex structure like media, software etc.
ZigBee Technology supports transfer of simple data like that from sensors. It supports low data rate of about 250 kbps. The operating frequencies are 868 MHz, 902 to 928 MHz and 2.4 GHz. ZigBee Technology is used mainly for applications requiring low power, low cost, low data rate and long battery life.In this project we are using 2530 module of zigbee which more reliable as compared to other module and provide high data capacity. Below is the features and specifications of 2530 module.1.
1.2.1 FEAUTERS:· As easy to use as any UART modules· Supports sending large data packet & fast broadcasting via UART· Supports programming via UART (thanks to the Bootloader, and an serial module is required)· Supports configuring via upper computer software· Auto networking (at least 1 Coordinator and 1 Router are required)· Real-time monitoring the signal intensity between Coordinator, Router, and End Device1.1.
2.2 SPECIFICATIONS:· Onboard chip: CC2530F256RHAR· Communication distance (open and wide operating environment):· Absolute maximum: over 350 meters· Stable communication: over 250 meters· Frequency range: 2.4GHz· Wide supply-voltage range (2 V–3.
6 V)· Operating temperature: -40? ~ 85?· Serial port baud rate: 38400bps (default), different baud rates are available by software configuration· Antenna: 2.4G 2DB 360° Omni-directional 1.1.3 MAX 232:MAX 232 is a kind of IC. It was created by maxim integrated products. It converts signals from the serial ports into the digital logic circuits.
It is a dual mode IC means it can receive or deliver the signals and perform desired functions on it. 1.1.
4 CRYSTAL OSCILLATOR:A gem oscillator is anelectronic oscillator circuit that uses the mechanical reverberation of a vibrating precious stone of piezoelectric material to make an electrical flag with an extremely exact recurrence. This recurrence is normally used to monitor time (as in quartz wrist watches), to give a steady clock flag to computerized coordinated circuits, and to balance out frequencies for radio transmitters and beneficiaries. The most well known sort of piezoelectric resonator utilized is the quartz precious stone, so oscillator circuits consolidating them ended up noticeably known as gem oscillators yet other piezoelectric materials including polycrystalline earthen ware production are byutilized as a part of comparable circuits. 1.1.5 DIGITAL HUMIDITY AND TEMPERATURE DEVICE (DHT):It will provide readings of ourdata transmission by the means of temperature reading. We use this device for testing purpose only we can also remove it when no longer needed.
1.1.6 REGULATOR 7805:This regulator converts the 12vol t to 5 volt which is suitable for aurduinoand LCD device attach to it.
This regulator is a part of our power supply.7805 series ICs have built-in protection against a circuit drawing too much power. They have protection against overheating and short-circuits, making them quite robust in most applications. In some cases, the current-limiting features of the 7805 devices can provide protection not only for the 7805 itself, but also for other parts of the circuit.
1.1.7 DIODES:A diode is basically device which give low resistance in one direction and high resistance in other direction. A very small amount of current in either way forward or backward flow run in the diode, because diode is reverse biased or forward bias depend on its type. A diode is a two terminal device In this project we use multiple diodes connected in series which has the function of rectify.
In this project we use it only for safety purpose. It converts AC to DC.1.1.8 CAPACITORS:A capacitor is basically an electrical component which have an ability to store electric charges. It filters the noise of Ac signal.A capacitor is basically passive electrical component and it is two terminal.
It store electrical charges in the form of potential energy. Capacitors and batteries both work in different way but they both store electrical charges. It is much like a small rechargeable battery.1.1.
9 RESISTERS:A resister is an electrical device that is used to produce resistance again the electrical charges. Resisters are passive electrical components.