A Comprehensive Study of RF Antennas
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International Journal of Pure and Applied Mathematics Volume 118 No. 9 2018, 755-764 ISSN: 1311-8080 (printed version); ISSN: 1314-3395 (on-line version) url: http://www.ijpam.eu Special Issue ijpam.eu A Comprehensive Study of RF Antennas Pawan Kumar1, Lavish Kansal2, *Gurjot Singh Gaba3, Mohammed Baz4 1,2,3School of Electronics & Electrical Engineering, Lovely Professional University, Punjab, India - 144411 4Computer Engineering Department, College of Computer and Information Technology, Taif University, Saudi Arabia – 26571 [email protected], [email protected], [email protected] *Corresponding Author – [email protected] Abstract—In this era the advent of radio frequency operated This part depicts the principle reconfiguration systems micro electromechanical systems is an empowering innovation utilized by RF MEMS reception apparatuses [2]. These for another era of astute receiving wires prepared to do systems are partitioned in outer arrangements, which utilize powerfully self-adjusting their properties and giving an enhanced tunable receiving wire bolsters, and interior methodologies, execution. These section examinations the distinctive which associate straightforwardly with the reception apparatus reconfiguration systems, covering outside methodologies in view of tunable nourishing systems, and interior methodologies which radiation instrument. change the radio wire radiation component. The part likewise depicts the primary utilizations of radio frequency operated II. RF COMMUNICATION SYSTEM micro electromechanical systems receiving wires, mechanical Detailed block diagram of RF communication system is points of view, outline contemplations and future patterns. depicted in Fig. 1.Source Keywords—RF communication model; Monopole antenna; Dipole antenna; Rectenna; Microstrip Antenna. Source is defined as a block that shares the data among the various subsystems. It generates the message data that is I. INTRODUCTION considered for analyzing the systems performance at the other part of the communication model. Nowadays the wireless technologies are continually advancing by giving high rate of information, lower costs, low A. Input transducer control utilization, compact gadgets. Reception apparatuses, as The input transducer converts the signal data which is radio-waves handsets, assume a basic part in this present in the physical form to the electrical form. It passes the advancement. Radio recurrence miniaturized scale electrical signal to the source encoding. electromechanical system (RF MEMS) is an empowering innovation for another era of insightful reception apparatuses B. Source encoder with the ability of powerfully self-adjusting their properties so Encoder is the circuit that converts the message bits from one as to keep up execution under operational or natural varieties. form to other form. In source encoding, sampling of the source RF MEMS is a magnificent innovation for the configuration of of information and quantization is done. Later on the source is receiving wire due to two fundamental properties. These are represented by the binary symbols or M-ary symbols. At receiver decoding of these received signals is done and they Unrivaled execution of RF MEMS switches and variable are filtered back to the analog signals. capacitors contrasted with their relating semiconductor gadgets. C. Channel Encoding The maximum transmission rate is set by the famous Remarkable coordination ability, empowering receiving Shannon capacity theorem. In this theorem the transmission wires with better execution and lower cost. reliability is quite high. In the presence of additive white Gaussian noise channel the representation is 755 International Journal of Pure and Applied Mathematics Special Issue C = B*log2(1+S/N) BER level) of the coded framework with the non coded framework Where C = channel capacity D. Modulator S = signal power N = Noise power In modulator the input is baseband signal and by passing that baseband signal through this block that baseband signal is In order to reach up to the limit of Shannon theorem is to use modulated so that it can travel to the longer distances. the codes for the error control because it enables us to transmit Modulation is defined as the process in which certain the messages reliably from one place to other. The channel properties of the waveform which is assumed to be periodic codes are classified into two main types. These are the and also known as carrier signal changes with respect to the convolutional and block codes. Another reason for using other waveform which is called the modulating signal. channel coding is the coding gain. Coding gain is defined as the difference of the signal to noise ratio (SNR) (at a certain Fig.1. Block diagram of RF communication system E. Channel H. Decoder The transmitted signal is now passed through the channel This block is used to convert encoded bits format to the which works as an intermediate between the transmitter and analog form. But here the signals will be still electrical the receiver. The channel may have a natural noise as well as signals. These signal are further transmitted to the Destination. the additive noise. The natural noise includes noise generated I. Output transducer due to the environmental factors like the rain and humidity. The additive noise may be the additive white Gaussian noise This block is used to convert the signal in the form of that is used in order to cancel the other noise. electrical to the physical form. The output we get can be in any physical quantity form. F. Demodulator J. Destination Demodulator is used to separate the carrier signal from the modulating signal that was added earlier in order to send the Destination is the location where we want to transmit the signal to the long ranges. It converts the signal to two different signal in the end. When the signal reaches the destination then signals i.e. modulating signal and carrier signal so that it can the whole process of RF transmission is over. The destination be analyzed at the destination point. can use the received signal for the analysis of the the message data like we can calculate the bit error rate as well the signal to G. Channel decoder noise ratio of the signal by comparing the received signal data Channel decoder is used to remove the redundant bits that with the signal data that was transmitted after the modulation were added earlier in order to increase the accuracy of the bits process. This help the system in improving its performance by or to check whether the bits we are transmitting are we getting removing the factors that reduce the information content of the them at the receiver. data. This can be done by applying the various techniques for error detection and error correction. 756 International Journal of Pure and Applied Mathematics Special Issue III. TYPES OF RF ANTENNAS Log-Periodic Dipole Array A. Log-Periodic Antennas Feed point Fig. 4. Representation of Log-Periodic Dipole Array Fig. 2. Log Periodic Antennas Log-periodic dipole array which includes various dipole An antenna which takes a shot at an extensive variety of components is the most well-known antenna that is utilized in frequencies is log periodic antenna and is a multi-component, wireless communication technology as depicted in Fig. 4. directional thin beam reception apparatus as shown in Fig. 2. From the back end to the front end the size of these dipole- With the help of succession of dipoles the log periodic antenna cluster radio wires decrease. These radio frequency receiving is composed that are set with the receiving wire pivot after wires main light beam is produced by the smaller size front certain interims of space in time that are superseded by end. The component at the back end of the cluster is huge in frequency function which is assumed to be logarithmic in size whose ½ of the wavelength is operating at low range of nature. Log periodic array is the other name referred to this frequency. Towards the front end of the array the distance type of antenna. This antenna provides a variable bandwidth between the element is decreased wherein the arrays which are together with the directivity and antenna gain. small in size are placed. Amid the working of this, as there is variation in the frequency, a smooth move happens along the Bowtie Antennas variety of the components, which prompts shape a dynamic area. B. Wire Antennas L + - D Fig. 3. Bowtie Antennas A bowtie reception apparatus is otherwise called Biconical radio wire or Butterfly receiving wire as shown in Fig. 3. Biconical radio wire is a wide band reception apparatus which is omnidirectional in nature. It has low response in terms of Fig. 5. Wire Antenna frequency which is considered as a measure for this receiving Wire antenna is the very basic type of antenna. These are wire, and goes about as a high-pass filter. If the frequency used in a large number of applications because of their goes as far as possible, far from the frequency of the outline, construction. Wire antennas are also referred by the name of the radiation shape of the reception apparatus gets twisted and curved and linear antennas as depicted in Fig. 5. These spreads. The greater part of the bow tie radio wires are reception apparatuses are additionally subdivided into four as subsidiaries of biconical reception apparatuses. clarified beneath. 757 International Journal of Pure and Applied Mathematics Special Issue Dipole Antenna The short dipole receiving wire is rarely palatable from a productivity perspective on the grounds that a large portion of the power entering this reception apparatus is dispersed as A Antenna Sections warmth and losses in the form of resistance likewise turn out to be continuously high. Monopole Antenna Radiating element Radiating element 2L L V V Fig. 6. Dipole Antennas Ideal Electric Conductor The most straightforward antennas includes dipole antenna as one of its type. When there is a sinusoidal voltage difference between the two thin metal rods it constitutes the dipole antenna as shown in Fig.