Free Essay

Analouge Radio Frequency

In: Other Topics

Submitted By masvin
Words 2561
Pages 11
Introduction: A network which freely passes desired band of frequencies while almost suppress other band of frequencies is called filter. This type of network was first examined by G.A Campbell and O.J Zobel of bell telephone laboratories. Filters are networks that process signals in a frequency-dependent manner. The basic concept of a filter can be explained by examining the frequency dependent nature of the impedance of capacitors and inductors. In filters, attenuation changes suddenly as the frequency is varied. Thus, filters have ability to discriminate between signals which differ in frequency.
Filters are widely employed in signal processing and communication systems in applications such as channel equalization, noise reduction, radar, audio processing, video processing, biomedical signal processing, and analysis of economic and financial data. For example in a radio receiver band-pass filters, or tuners, are used to extract the signals from a radio channel. In an audio graphic equalizer the input signal is filtered into a number of sub-band signals and the gain for each sub-band can be varied manually with a set of controls to change the perceived audio sensation. In a Dolby system pre-filtering and post filtering are used to minimize the effect of noise. In hi-fi audio a compensating filter may be included in the preamplifier to compensate for the non-ideal frequency-response characteristics of the speakers. Filters are also used to create perceptual audio-visual effects for music, films and in broadcast studios.
The primary functions of filters are one of the followings: To confine a signal into a prescribed frequency band as in low-pass, high-pass, and band-pass filters. To decompose a signal into two or more sub-bands as in filter-banks, graphic equalizers, sub-band coders, frequency multiplexers. To modify the frequency spectrum of a signal as in telephone channel equalization and audio graphic equalizers. To model the input-output relationship of a system such as telecommunication channels, human vocal tract, and music synthesizers. Investigates various type of filter:

Radio frequency filter:

An RF (radio frequency) filter is a device that is utilized to allow or stop selected signals or frequencies, or used to eliminate (filter out) any unwanted signals. In other words, an RF filter is designed to allow for the attenuation or transmission of a range of frequencies that would be applied. For instance, an RF filter helps to cut out RF interference that could occur if a hairdryer, lamp, or other "noisy" device is activated.
Generally, there are four types of RF filters:

A high pass filter has a cut-off frequency, thereby allowing minimal or no loss in transmission for high frequencies, but considerably attenuating any low frequencies. A low pass filter is the opposite that of a high pass filter - that is, allowing for the transmission frequencies below the cut-off frequency, but attenuating any frequencies above the cut-off frequency. A band pass filter will allow for the transmission of a selected range or band of frequencies with no attenuation, but will attenuate frequencies below or above(lower or higher than) the desired or allowed band. Examples of band pass filters include cavity filters, surface acoustic wave (SAW) filters and crystal filters. A band reject filter will attenuate a frequency range or band while allowing all other frequencies to pass un attenuated. Examples of band reject filters include notch filters and band stop filters.

Various types of RF filters can be found in air traffic control and communications systems, medical alert systems, telemetry applications, two-way pagers, and satellite communications. Other uses include garage door openers, fire control radars, keyless locks, and radar and missile guidance systems.
Microwave filters:

Microwave Filters are two-port networks used to control the frequency response in a system by permitting good transmission of wanted signal frequencies while rejecting unwanted frequencies. Generally there are four types of filters. They are, Low-pass High-pass Band-pass Band-stop.
Microwave filter design has been a persistent and productive field for investigation from the very beginning of microwave engineering. Nowadays, high performance filters are needed in many microwave systems. Because of the importance of microwave filters, a great deal of material on the theory and design of filters is widely available in the literature. The purpose of this chapter is to introduce the basic theory of microwave filters, to describe how to design practical microwave filters, and to investigate ways of implementing high performance filters for modern communication systems.
Passive filters:

In passive filters, passive elements such as resistors, capacitors and inductors are used. The disadvantage of passive filter is the inductors are heavy and bulky and hence passive filters become costly. However they do not require additional power supplies for their operation. The range of frequencies over which attenuation by filter is called pass band. The range of frequencies over which attenuation is infinite is called stop band or attenuation band of the filter. Butterworth Filters Chebyshev Filters Bessel Filters Elliptical Filters
Butterworth filter:

The Butterworth filter is a medium-Q filter that is used in designs that require the amplitude response of the filter to be as flat as possible. The Butterworth response is the flattest passband response available and contains no ripple. Since the Butterworth response is only a medium-Q filter, its initial attenuation steepness is not as good as some filters but it is better than others. This characteristic often causes the Butterworth response to be called a “middle-of-the-road” design.
The attenuation of Butterworth filter is given by,
A_(dB=10 10g[ 1+( ω/ωc)2n])
Where:
ω = the frequency at which the attenuation is desired ωC = the cutoff frequency ω(3dB) of the filter n = the number of elements in the filter In most cases for Butterworth filters, ωc is defined as the frequency of the 3-dB pass band edge point. Figure:1 Butterworth low pass filter

Chebyshev filters:

The Chebyshev filter is a high-Q filter that is used when: A steeper initial descent into the stop band is required The pass band response is no longer required to be float.
With this type of requirement, ripple can be allowed in the pass band. As more ripples is introduced, the initial slope at the beginning of the stop band is increased and produces a more rectangular attenuation curve when compared to the rounded Butterworth response. Both curves are for n = 3 filters. The Chebyshev response shown has 3 dB of pass band ripple and produces a 10-dB improvement in stop band attenuation over the Butterworth filter. The poles would lie on an ellipse of the unit circle. That means that like Butterworth filters, Chebyshev filters contain only poles. However, while the poles of the Butterworth filter lie on a circle in the s-plane, those of the Chebyshev filter lie on an ellipse. The Chebyshev phase response exhibits more linearity than the Elliptic one and less linearity than the Butterworth one. Figure:2 chebyshev low pass filter

Elliptical filters:

Another name for the Elliptic Filter is ’Cauer’ filter. Compared with Butterworth and Chebyshev filters, Elliptic filters have the most rapid transition (narrow transition band). However, this does not come without a price. Elliptic filters have a ripple in both the pass band and stop band. This is the result of a pole-zero configuration which consists of both poles and zeros. An Elliptic filter is notorious for introducing large phase distortions, especially near the edge of the pass-band where the sharp amplitude characteristic implies a strongly non-linear phase characteristic. Figure: 3 elliptical low pass filters
Bessel filters:

Butterworth filters have fairly good amplitude and transient behavior. The Chebyshev filters improve on the amplitude response at the expense of transient behavior. The Bessel filter is optimized to obtain better transient response due to a linear phase (i.e. constant delay) in the pass band. This means that there will be relatively poorer frequency response (less amplitude discrimination).The poles of the Bessel filter can be determined by locating all of the poles on a circle and separating their imaginary parts by: 2/n where n is the number of poles. Note that the top and bottom poles are distanced by where the circle crosses the jω axis by: 1/nor half the distance between the other poles. Design procedure of the filter:

The various type of performances of passive filters has been investigated above and the Bandpass filter has been designed below by using chebyshev filter design with pass band ripple of 1.0 dB with theses specifications:

Parameter Units
Centre frequency 200 MHz
Bandwidth 20 MHz
Return loss @ Centre frequency < - 10 dB
Attenuation < -48 @ 150 MHz and 250 MHz
VSWR ≤ 2

Table:1 parameters and units
Given,
Centre of frequency fc = 200 MHz,
Attenuation < -48 @ 150 MHz and 250 MHz
Bandwidth = 20 MHz
BPF = (250-150)/4 = 5

Figure 4: Attenuation characteristics for a chebyshev filter with 1.0 dB ripple.

Where BPF = 5 and the attenuation is – 48
By using this table, it has been found, n = 3
Take RS = 50 ohm and
RL = 50 ohm
RS/ RL = 50 / 50
= 1

Figure: 5 chebyshev low pass element values for 1.0 dB
Look at the table, Where n = 3 and Rs/RL = 1
So the values are,
C1 = 2.216
L2 = 1.088
C3 = 2.216

Low pass filter prototype design:

Figure: 6 prototype of chebyshev low pass filter

Transformation low pass to Bandpass filter:

Figure: 7 transformation of low pass filter to Bandpass filter.

The values had been calculated for capacitance and inductance by using parallel resonant branch and series resonant branch formulas:
Parallel resonant branch:
C = cn/(2πRL Bw 3dB)
L = (RL Bw 3 dB)/(2πLnfc^2 )
Series resonant branch:
L = RlLn/(2π Bw 3dB)
C = (Bw 3dB)/(2π Cn fc^2 Rl)
Where parallel resonant branch are,
C1 = 2.216
L1 = 2.216
C3 = 2.216
L3 = 2.216

Parallel resonant branch:

C1 = cn/(2πRL Bw 3dB)
C1 = 2.216/(2π*50*20MHz )
C1 = 352. 687 Pf
L1 = (RL Bw 3 dB)/(2πLnfc^2 )
L1 = (50* 20MHz)/(2π*2.216〖*(200MHz)〗^2 )
L1 = 1.795nH
C3 = cn/(2πRL Bw 3dB)
C3 = 2.216/(2π*50*20MHz )
C3 = 352.687pf
L3 = (RL Bw 3 dB)/(2πLnfc^2 )
L3 = (50* 20MHz)/(2π*2.216〖*(200MHz)〗^2 )
L3 = 1.795nH
Series resonant branch:
L = RlLn/(2π Bw 3dB)
L2 = (50*1.088)/(2π*20MHz)
L2 = 432.901nH

C2 = (Bw 3dB)/(2π Cn fc^2 Rl)
C2 = 20MHz/(2π*1.088* (200MHz)^2 50)
C2 = 1.462pf
Complete chebyshev Bandpass filter design is shown below

Figure: 8 the complete circuit design

Simulation and results:

Figure: 9 filter design by using rfsim 99 software

Figure 10: complete chebyshev Bandpass filter design.

Figure: 11 the Bandpass filter design for 1dB chebyshev filter
Centre frequency:
According to the given parameters the Centre of frequency is 200 MHz Figure: 12 Centre frequency of Bandpass filter
The start band is at 150MHz and stop band at 250MHz.
Where f= 200.1MHz at -0.0072dB
Therefore, it achieves the give requirements.
Bandwidth:

Figure: 13 bandwidth diagram
The attenuation of -3dB at f1 = 190.481MHz
The attenuation of -3dB at f2 = 210.521 MHz
Bandwidth = f2-f1
= (210.521MHz) – (190.481MHz)
= 20.04MHz
So, it achieves the given requirement bandwidth of 20MHz
Return loss @ Centre frequency:

Figure: 14 return loss
Return loss should be < -10
Here, it gets -42.69dB.
Calculation for VSWR:

Return loss = -42.69 dB
20 log = - 42.69 dB
〖 log〗^(-1)= -42.69dB/20
〖 log〗^(-1) = - 2.1345
= 0.00733
VSWR = 1 + 0.00733/ 1- 0.00733
VSWR = 1.01
The given VSWR is ≤2
Therefore the VSWR is also achieves the given requirements.

Q- factor: (f2-f1)/Bw
= ((210.521MHz)-(190.481))/20MHz
= 20.04MHz/20MHz
= 1.0012
Alternate filter designs:

Insertion loss method:

The insertion loss method allows a high degree of control over the pass band and stop band amplitude and phase characteristics, with a systematic way to synthesize a desired response. The necessary design tradeoffs can be evaluated to best meet the application requirements. If, for example, a minimum insertion loss is most important, a binomial response could be used; a Chebyshev response would satisfy a requirement for the sharpest cutoff. If it is possible to sacrifice the attenuation rate, a better phase response can be obtained by using a linear phase filter design. And in all cases, the insertion loss method allows filter performance to be improved in a straightforward manner, at the expense of a higher order filter. For the filter prototypes to be discussed below, the order of the filter is equal to the number of reactive elements.

Given, Centre of frequency fc = 200 MHz,
Attenuation < -48 @ 150 MHz and 250 MHz
Bandwidth = 20 MHz
BPF = (250-150)/4 = 5

Figure 15: Attenuation characteristics for a chebyshev filter with 0.5 dB ripple.
Where BPF = 5 and the attenuation is – 48
By using this table, it has been found, n = 3
Take RS = 50 ohm and
RL = 50 ohm
RS/ RL = 50 / 50 = 1

Figure: 16 elements values for chebyshev 0.5dB low pass filter

From the table 15 the elements values for low pass filter prototype circuit are given us, gl = 1.5963 = L1, g2 = 1.0967 = C2, g3 = 1.5963 = L3, g4=1.000 =RL

The ratio of 0.5dB ripple is
Center frequency is 200MHz and the bandwidth is 20MHz
So the ratio is ∆=0.1

A series inductor is transformed to a series LC circuit with impedance and frequency scaled values,

A shunt capacitor is transformed to a shunt LC circuit with impedance and frequency scaled values,

Where, ∆ =0.1
R_(0=) 50 ohm ω_(0=2π200MHz) L1 = (1.5963*50)/(2π*200MHz*0.1) = 635.14nH

C1 = 0.1/(2π*200MHz*1.5963*50) = 0.9777pF

L2 = (0.1*50)/(2π*200MHz*1.0967) = 3.62nH

C2 = 1.0967/(2π*200MHz*0.1*50) = 174.5pF

L3 = (1.5963*50)/(2π*200MHz*0.1) = 635.14nH

C3 = 0.1/(2π*200MHz*1.5963*50) = 0.9777pF

Figure: 17 Band pass circuit design

Figure: 18 the Bandpass filter design for 0.5dB chebyshev filter by insertion loss method

Center of frequency:
According to the given parameters the center of frequency is 200MHz.

Figure: 19 Centre frequency of Bandpass filter
The start band is at 150MHz and stop band at 250MHz.
Where f= 200MHz at -0.0000042dB
Therefore center of frequency is = 0

Bandwidth:

Figure: 20 bandwidth diagram
The attenuation of -2.93dB at f1 = 188.677MHz
The attenuation of -2.88dB at f2 = 211.924 MHz
Bandwidth = f2-f1
= (211.924MHz) – (188.677MHz)
= 23.24MHz

Return loss at center of frequency:

Figure: 21 return loss
Return loss should be < -10
Here, it gets -42.94dB

Calculation for VSWR:

Return loss = -42.94 dB
20 log = - 42.94 dB
〖 log〗^(-1)= -42.94dB/20
〖 log〗^(-1) = - 2.147
= 0.00712
VSWR = 1 + 0.00712/ 1- 0.00712
VSWR = 1.01
The given VSWR is ≤2
Therefore the VSWR is also achieves the given requirements.
Q-factor:

(f2-f1)/Bw
= ((211.924MHz)-(188.677))/20MHz
= 23.24MHz/20MHz
= 1.162

Evaluate performances of both designs:

Parameters Units Main design Alternative design
Center frequency 200MHz 200.1MHz at -0.0072dB 200MHz at -0.0000042dB

Bandwidth 20MHz 20.04MHZ 23.04MHz
Center frequency at return loss…...

Similar Documents

Premium Essay

Radio Frequency

...Radio Frequency Identification system Riordan Manufacturing Radio Frequency Identification (RFID) is a widely used wireless device to scan products. It is a non contact wireless device, which uses radio frequency electromagnetic fields that transfer data from a unique tag placed on products for purchase. Tags will be placed upon every item which will include raw materials, plastic beverages, cooling fans, stents, bottles, and storage containers. This device is non contact unlike the bar code technology, RFID removes the need to have straight line contact like the bar code requires. TH RFID can scan from distances as far as 100 feet. The hardware consists of an antenna and a transceiver. Both of these hardware’s read and delivers the information to a processing device. This streamlines the tracking process throughout the ordering and shipping process. Sales department fills the order and enters the data into the billing and shipping system. At this point the order goes on to the customer shipping department where it is processed for shipment and then loaded on to the delivery truck. All of the items shipped on a daily basis are updated by time and date, and truck number the order has been shipped on. Several benefits come from an RFID system. The enhancement of the supply chain visibility will deliver more efficiency, speed, and allows for tracking products throughout the shipment process. In addition, reducing costs due to efficient waste management. The RFID has many......

Words: 286 - Pages: 2

Free Essay

Frequency

...Checkpoint in your own words IT/241 Intro to W-Lan technologies FRED HOLMES IV April Sturgess Friday May 4, 2013 What is frequency? Frequency is the number of cycles of a repeating signal. The unit of frequency is measured in hertz. Each hertz is equal to one cycle of an event in seconds. For a frequency to be considered an audio frequency it has to be between 15 Hz and 20000 Hz. A radio frequency will range from 20 kHz to 1 terahertz. A medium for radio frequency will be air and metal. Air will not conduct electricity so the displacement won’t happen. When it comes to infinity value, air will become resistant and only some current flow will go through. Metal is an electricity conductor. This means that the flow will be based on the resistance of metals and the components with in the metal. What is analogue modulation? Is the information which is applied to the carrier signal. This is usually with radio signals. The amplitude modulation will change any frequency of the signal. Frequency Modulation is the frequency of the Carrier can wave at the input signal with the level use multiple methods When comparing the modulation we can show that both use the same method. The only difference is that digit. While this process is going on the digital modulation can use multiple times. Digital will also apply filters to......

Words: 264 - Pages: 2

Free Essay

Radio Frequency (Rf) Interference Analysis and Optimization

...Radio Frequency (RF) Interference Analysis and Optimization By Farhana Jahan ID: 061-19-342 Md. Rafiqul Islam ID: 061-19-370 Md. Mohibul Hasan ID: 061-19-373 A thesis report presented in partial fulfillment of requirements for the degree of Bachelor of Science in Electronics and Telecommunication Engineering Supervised by Mohammed Humayun Manager (Network Department) ADVANCED DATA NETWORKS SYSTEM LIMITED Red Crescent Concord Tower (19th floor) 17, Mohakhali Commercial Area, Dhaka-1212 Department of Electronics and Telecommunication Engineering DAFFODIL INTERNATIONAL UNIVERSITY October 2009 i APPROVAL PAGE This thesis titled „Radio Frequency (RF) Interference Analysis and Optimization‟, Submitted by Md. Rafiqul Islam, Md. Mohibul Hasan and Farhana Jahan to the Department of Electronics and Telecommunication Engineering, Daffodil International University, has been accepted as satisfactory for the partial fulfillment of the requirement for the degree of Bachelor of Science in Electronics and Telecommunication Engineering and approved as to its style and contents. The presentation was held on 19th October 2009. Board of Examiners Mr. Golam Mowla Choudhury Professor and Head Department of Electronics and Telecommunication Engineering Daffodil International University ---------------------(Chairman) Dr. M. Lutfar Rahman Dean & Professor Faculty of Science and Information Technology Daffodil International University ---------------------(Member) A K M......

Words: 18928 - Pages: 76

Premium Essay

Radio Frequency Based Remote Controlled Robot with Wireless Video Camera Mounted on It

...RADIO FREQUENCY CONTROLLED INTELLIGENT ROBOT Saradindu Naskar Department of Computer Science, St. Xavier’s College Kolkata, India Email: saradindu.naskar@gmail.com Abstract ─ My military robot has got two barrel turret through which bullet can be fired; radio camera in synchronization with the turret can rotate up and down, left and right up to a safe firing limit. Turret and camera mechanism has been installed on my robot vehicle, which has all the function like tank, turning to any angle on its axis, moving forward and reverse turning left and right, running instantly into reverse direction. This robot is radio operated; self powered, has image processing facility and has all the controls like a normal car. A pair of laser gun has been installed on it, so that it can fire on enemy remotely when required; this is not possible until a wireless camera is installed. Wireless camera will send real time video and audio signals which could be seen on a remote monitor and action can be taken accordingly. It can silently enter into enemy area and send us all the information through its tiny Camera eyes. It is designed for, fighting as well as suicide attack. Keywords─ISO, robot, DARPA, DSTA, RF, cockroach intelligence. or mobile for use in industrial automation applications. “ All these definition do give us a rough idea about what comprises a robot, which needs to sense the outside world and act accordingly. There are motors, pulleys, gears, gearbox, levers, chains, and......

Words: 2618 - Pages: 11

Premium Essay

Radio Frequency Identification Devices

...Allaire Webster Case 1 Radio Frequency Identification Devices (RFIDs) are small chips used to track inventory through radio transmissions and are powered by radio signals similar to that of a cell phone. This technology is fairly new. In 2003 Walmart started testing the use of RFID tags on its merchandise for inventory control. RFID tags can be placed anywhere on most items and are readable even when covered with packing materials, dirt, or plastic bands. Bar codes must be visible to be scanned. A bar code scanner must be placed within a few inches of the bar code. Most RFID readers have a range of about six feet. RFID tags are small enough to be installed on the face of credit cards or sewn into clothing items. Using RFID technology can greatly benefit Harley Davidson. RFIDs can track inventory much faster. RFID offers a range from inches to hundreds of feet. With using RFIDs means you do not have to open each box. Individual tags within a carton packed in a box stored on a pallet may be read. RFID can also store much more data than a bar code. RFIDs have read and write capabilities, unlike barcodes, mistakes are less likely and maintaining accuracy is consistent. Using RFID helps manage inventory by making sure that items are stocked and available for the customers. It also improves processing time in terms of ordering needed supplies. RFIDs do have flaws. The cost of implementing RFID in a large company like Harley Davidson would be high.Harley Davidson would......

Words: 415 - Pages: 2

Premium Essay

Johnson & Johnson Philippines Inc. Logistics Park: with the Introduction of Radio Frequency Scanner and Track, Trace, Scan and Send (T2S2) in Streamlining the Whole Supply Chain Processes

...process: * More paper works * Unmet delivery expectation | Introduce a Radio Frequency Scanner (RFS) to improve inventory process and Track Trace Scan and Send device (T2S2) to monitor delivering of finished goods to distributors. | IV: Design of the Proposed System We strongly propose to transfer the National Distribution Center to the place where the Raw and Packaging Materials Warehouse and the Manufacturing Warehouse are located to make the place become a Logistics Park. The first building is for the raw and packaging materials warehouse and for the manufacturing. It is divided by a movable wall so that when there is a need for additional space in the warehouse, the space in the manufacturing will be allotted for it. The other building is for the Finished Goods Warehouse. It is connected to the other building so that the transfer of goods from manufacturing to finished goods warehouse is done with the use of forklifts. Proposed Logistics Park: Parañaque Upon the arrival of the goods from the supplier, items will be received at the Raw and Packaging Materials Warehouse. It will be stored in the warehouse until the items were ordered by the Third Party Manufacturer. Items ordered by the Manufacturer will be transferred through forklift. Finished goods from the manufacturing are also transferred through forklift to the Finished Goods Warehouse. With this system, we propose the use of Radio Frequency Scanner to monitor the movement of the goods in every area of......

Words: 3998 - Pages: 16

Premium Essay

Radio Frequency Identifications Tags

...Radio Frequency Identifications Tags II. RFID tags have many advantages. A. RFID tags enhance product visibility which facilitates operations. They are made rugged and robust; therefore; they can be used in harsh environments and temperatures. There no positioning problems with RFID tags, they can be place anywhere and do not require a line-of sight to be scanned. B RFID tags reduce cost. The RFID system reduces the labor cost of the company by providing a good tracking system. This technology can be effective in stock management. It helps to reduce the misplacement of goods because it’s easier to trace. C. RFID tags reduce losses and theft. The use of RFID tags in retail stores are used to keep track of high priced items, to prevent theft. RFID tags easily track moving objects and send the required information back to the reader. III. RFID tags are used in a variety of ways. A. RFID tags have a longer read range and can be scanned on the factory floor from forklifts and scanners at a distance. This technology is used in the manufactory industry. There are no positioning problems with an RFID tag, they can be placed anywhere. B Injectable RFID tags can be used for tracking animals easily. These tags have information about the animal’s, medical history and vaccinations. Information written on the tags cannot be duplicated easily. C. RFID tags are being used to reduce truancy and improve safety in schools. Each child......

Words: 452 - Pages: 2

Free Essay

Radio Frequency Based Remote Controlled Robot with Wireless Video Camera Mounted on It

...Radio Frequency Based Remote Controlled Robot with Wireless Video Camera Mounted on It In: Science Radio Frequency Based Remote Controlled Robot with Wireless Video Camera Mounted on ItRADIO FREQUENCY CONTROLLED INTELLIGENT ROBOT Saradindu Naskar Department of Computer Science, St. Xavier’s College Kolkata, India Email: saradindu.naskar@ gmail.com Abstract ─ My military robot has got two barrel turret through which bullet can be fired; radio camera in synchronization with the turret can rotate up and down, left and right up to a safe firing limit. Turret and camera mechanism has been installed on my robot vehicle, which has all the function like tank, turning to any angle on its axis, moving forward and reverse turning left and right, running instantly into reverse direction. This robot is radio operated; self powered, has image processing facility and has all the controls like a normal car. A pair of laser gun has been installed on it, so that it can fire on enemy remotely when required; this is not possible until a wireless camera is installed. Wireless camera will send real time video and audio signals which could be seen on a remote monitor and action can be taken accordingly. It can silently enter into enemy area and send us all the information through its tiny Camera eyes. It is designed for, fighting as well as suicide attack. Keywords─ISO, robot, DARPA, DSTA, RF, cockroach intelligence. or mobile for use in industrial automation applications. “ All these......

Words: 347 - Pages: 2

Free Essay

Radio-Frequency Identification Essay

...R.F.I.D. (Radio-Frequency Identification) RFID is the wireless non-contact use of radio-frequency electromagnet fields to transfer data. RFID tags are used in many industries to enter or exit buildings as well as buy certain things (mostly use in the government). It can also be attached to cash, clothing, and everyday possessions (such as cell phone, Laptops, desktop computers, tablets, etc.). Let me give you some history about where this technology came from In 1945 Leon Theremin invented an espionage or spying tool for the Soviet Union which retransmitted incident radio waves with audio information. Sound waves vibrated a diaphragm, which slightly altered the shape of the resonator that modulated the reflection radio frequency. So basically Leon Theremin created the processor for the RFID technology because it is being energized and activated by waves from an outside source. RFID uses signaling between the reader and tag is done in several different incompatible ways its all depending upon the frequency band being used. Tags operate on LF and HF bands, which use small radio waves to transmit signals. In the near electromagnetic field region the tag is closely combined electronically with the transmitter in the reader. The tag can increase the electromagnetic field created by the reader by changing the electrical loading. By changing the relative loads higher or lower the tag produces a change that the reader can......

Words: 287 - Pages: 2

Premium Essay

Radio

...RADIO FREQUENCY IDENTIFICATION Introduction RFID is a technology which enables detecting and identifying objects using electromagnetic radio waves. This is processed through exchange of information between a reader and a tag being attached to the object that includes the data associated with the object. This can be used to detect and classify vehicles, animals, patients, shipment goods and airline baggage. [1] RFID technology involves two main components, they are transponders which are also known as tags or labels, contain the relevant information about the object and other the interrogators, also known as readers or transceivers, that extract the data from the tags. These tags can be passive or active tags. Passive tags use the energy from the EM radiation of the reader for its processing, where as active tags receive power from an internal battery for its processing and communication with the reader. An integrated electronic circuit is embedded in tags for storage and processing operations and an antenna that transmits and receives the RF signal. [2] Figure : components of RFID Source : http://www.docstoc.com/docs/17328767/Draft-SP800-98 The tags used in RFID are enabled with read-write operations, with a large storage capacity. Data can be modified any number of times. Tag and reader act as two way radio communication in which each antenna carries the modulation and demodulation of RF signals, with operation frequency ranges from low frequency to UHF. As......

Words: 939 - Pages: 4

Premium Essay

Radio Frequency Identification (Rfid)

...Running head: RADIO FREQUENCY IDENTIFICATION Radio Frequency Identification (RFID) Esther Olayinka Olagbaju November 27, 2011 Chamberlain College of Nursing Introduction Radio frequency identification (RFID) is a generic term that is used to describe a system that transmits the identity (in the form of a unique serial number) of an object or person wirelessly, using radio waves. It is in use all around us; from the chips inserted in pets as an ID tags, to the EZPass through a tollbooth. In short, this technology does not require contact or line of sight for communication. RFID data can be read through the human body, clothing, and non-metallic materials (AIM, 2011). As a member of the committee created by the Government to investigate the potential of implanting an electronic record (EHR) into every U.S. citizen, this research will look into the benefits of this business decision to the Government, and then we will analyze the advantages and disadvantages of RFID being implanted under the human skin, which is then followed up by the laws governing this action if it can be enforced or voluntary based procedure, and finally the percentage of people that will be willing to go through this procedure. Body of Analysis Radio frequency identification technology is slick and easy to manage and also comes in three general varieties, namely; passive, active, and semi-passive (also known as battery-assisted). Passive tags need no internal power source and are only active......

Words: 849 - Pages: 4

Premium Essay

Radio Frequency Identification (Rfid) Technology in Construction Industry

...Radio frequency identification (RFID) technology is currently being used in such areas as agriculture, athletics, manufacturing, security and law enforcement, and transportation, but few applications have been developed that are related to the construction and facilities operations environment. Lack of standardisation, high costs of implementation, slow technology development and deployment risks, and the lack of skilled labour are all contributors currently preventing the adoption of new RFID technologies in the construction industry. The RFID technology can help improve data accuracy by tracking products through supply chains and by identifying products and items/objects at specific points through Automatic Identification (Auto-ID). The technology enables the detection and identification of tagged objects through the data it transmits. Objective of this topic ‘RFID IN CONSTRUCTION’ is to get an overview of the present application of RFID technology in Construction. Radio Frequency IDentification (RFID) is an old technology which was already in use for recognition for anti-aircraft gun shooting in World War. Since then RFID has been taken into use for many other purposes, i.e. securing against theft of goods, bridge crossing fees, car keys etc. The new importance of RFID is connected to certain measures which a group of the world’s biggest retail chains and brand suppliers initiated under the name of Global Commerce Initiative at the end of the 1990’es. The......

Words: 546 - Pages: 3

Free Essay

Radio

...Radio Script 1) RADIOHEATWAVE TOP OF THE HOUR (TOH) SWEEPER (est. 19sec) Bring down the Netia A fader SLIGHTLY & GRADUALLY in order to talk above volume levels of the TOH music. If not, your voice will be drowned out! Intro (hottest campus radio station…): *ON MIC* Hey, it’s Jocelyn on Radio Heatwave, this is Love Dose. And you know what, coming up on today’s show, I’m going to share with you three tips for your first date. Meantime though, This is Marvin Gaye by Charlie Puth Featuring Meghan Trainor only on the hottest thing on campus (Radio Heatwave). *OFF MIC* Music #1 – Marvin Gaye – Charlie Puth Featuring Meghan Trainor (3 min 6 sec) (Until the dawn, let’s Marvin Gaye and get it on WOO) *ON MIC* Talk set #1: That was Marvin Gaye by Charlie Puth Featuring Meghan Trainor … You’re on Love Dose with me, Jocelyn, on Radio Heatwave! Meghan Trainor and Charlie Puth’s (POOFS) make out session after their performance together at the recent American Music Awards was the most O-M-G moment! Hmm, talk about Lips are Moving… according, to sources close to them, they’re really good friends and the whole make out session was actually rehearsed and planned! But regardless, let’s Marvin Gaye and get it on! Coming right up, I’ll be sharing the three tips for your first date! And if you have been Waiting for Love just like this song by Avicii, well, you got to stay with me on Radio Heatwave. *OFF MIC* Music #2 – Waiting for Love – Avicii (3 min...

Words: 627 - Pages: 3

Premium Essay

Radio Frequency Identification

...Overview For the technical requirement of the V-Bullet system we analyze the size, speed, range, security and some other major standards. The major parts of the system are the tag chips, readers, communicational network, the middleware, the server, the database, and the web-based user interface. RFID Tag For the RFID tag we decided to use a passive chip over an active one because passive tags are cheaper, they have longer lifespan and they are smaller than active tags; besides, Active tags are more useful for locations based applications and others identity applications purposes which we don’t need. This passive chip will be ensemble on a smart card with a convenient size that can fit into a wallet. The RFID tag must be in compliance with the ISO standards and will become a V-Bullet tag chip that will count with anti-cloning measures, and utilize strong encryption during communication with the reader. RFID Reader We select a reader that complies with the ISO standards and it is assumed that the readers will be used in a very noise environment that can be dusty and have high humidity depending on the location of the station, also it is important that these readers have an operating temperature between -13 and 174 degrees Fahrenheit. We know how far the reader would be from the tags but we can’t control the orientation and position of the tags; therefore, we decide to select a reader with ISO standards capable to work with circular antennas which are able...

Words: 1154 - Pages: 5

Free Essay

Age of Radio

...The Age of the Radio Radio has always been one of the most powerful media sources available. It goes without saying that it is popular due to the fact that the necessary equipment, radio transmitter and receiver. Radio was the start to worldwide communication. There were many inventors to thank for the radio. In 1860, James Maxwell predicted the existence of radio waves (Bellis). James Maxwell formulated a set of equations, which explained light as one form of electromagnetic radiation and predicted that there should be many other forms, invisible to the human eye. Heinrich Hertz demonstrated that rapid variations of electric current could be projected into space (Bellis). Fortunately, other scientist and engineers saw the radio spectrum not as a curiosity but as a tool for a new kind of communication. Guglielmo Macroni proved the feasibility of radio communication. In 1895, Macroni sent the first radio signal. With further alterations, Macroni found a way for ships to talk to each other using Morse code. The next big step was finding a way to manipulate radio waves so they could carry more than dots and dashes. Switching from pulses to continuous waves provided the key. Reginald Fessenden invented a way to transmit voice by altering the intensity of waves, thus creating AM radio. Reginald Fessenden noticed that by varying wave frequency instead of amplitude, stations could avoid the interference that often corrupted AM transmissions. The result was frequency modulation......

Words: 1647 - Pages: 7

2019 Wall Calendar, Babes Big Print Calendar by Bartel | Cartoonstitute | Angry Birds 2 2.25.1