DOCSLIB.ORG

Bayesian Detection of Wi-Fi Transmitter RF Fingerprints

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Bayesian Detection of Wi-Fi Transmitter RF Fingerprints Bayesian detection of Wi-Fi transmitter RF using data collected from a number of Wi-Fi radios and it is shown that fingerprints its performance is better than that of the step change detector in detecting the turn-on transients of Wi-Fi radios. O. Ureten and N. Serinken Signal model: Typical transmission data, such as that shown in Fig. 1, A transient detection technique is presented for the detection of the contain ambient channel noise followed by the start of a radio transmis- turn-on transients of Wi-Fi radios. The turn-on transients are detected sion. Data samples form a piecewise signal, which can be modelled as: by a Bayesian change detector, which estimates the time instant when the transmitter starts to power up. The proposed technique is verified m þ u if 1 i < m with the transient data collected from a number of Wi-Fi radios and it d ¼ i ð1Þ i m þ aði À mÞþu if m i N is shown that the ramp detector outperforms the abrupt change i detector in detecting the turn-on transients of Wi-Fi transmitters. where di is the data sample at time instant i, N is the number of data points, m is the change point, m is the mean of the samples before the Introduction: In military and civilian spectrum management operations, change point, a is the slope of the linear ramp-up and u is a zero-mean identification of a specific RF transmitter is often used in traffic analysis white Gaussian process with a standard deviation of s. The model or in the determination of sources of interference. As wireless platforms assumes a linear increase in the power level of the radio during start-up. grow in popularity and store valuable information, attacks on such The model can be written in the form of a matrix equation: systems are increasing. These RF attacks can take the form of intrusion, disruption of services, theft of bandwidth and=or denial of service. d ¼ Gb þ e ð2Þ To improve the safety and security of mobile VHF radio networks, where d is an N Â 1 matrix of data points and e is an N Â 1 matrix of transmitter identification systems relying on the unique turn-on char- Gaussian noise samples. The matrix G is of size N Â M. Each column acteristics of the radios have been reported [1]. The unique turn-on of G is a basis function evaluated at each point in the time series and characteristics are called ‘RF fingerprints’, and can be applied to each element of the M Â 1 matrix b is a linear coefficient. The wireless systems, such as 802.11x, to identify individual transmitters. a posteriori probability density of the change point given the data Security of wireless networks can be enhanced by challenging a user to and the signal model is calculated as [4] prove its identity if the fingerprint of a network device is unidentified or deemed to be a threat. Access to services could also be restricted or ½dTd À dTGðGTGÞÀ1GTdðNÀMÞ=2 interference could be reduced by smart antennas. pðfmgjd; IÞ/ pffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi ð3Þ detðGTGÞ RF fingerprinting from the turn-on transients requires three stages: detection of the turn-on transients, extraction of the characteristic features where I denotes the signal model defined in (1). The change point of the transients and classification of the fingerprints. The performance of position is built into the structure of the matrix G and for a ramp change the detection stage is significant because inaccurate detection adversely it can be written as: affects the feature extraction stage thereby reducing classification perfor- mance. The objective of the detection stage is to determine the exact time 11111... 1111... 1 GT ¼ ð4Þ instant when the transmitter is turned on. In the case of VHF radios, 00000... 0123... N À m detection of the turn-on transients is based on the change point detection principle, in which the detector determines the instant when the received The a posteriori probability in (3) can be evaluated using only the data power level exhibits a sudden increase. The abrupt change detector values without the knowledge of the noise level s or any other linear system was used successfully for VHF radios where there is a sudden parameter in b (m and a). The maximum a posteriori (MAP) estimate of change in the power level at the transition from the channel noise to the the change point is then obtained by finding the index of the maximum turn-on instant of the radio [2]. However, the Wi-Fi standard specifies that of the a posteriori probability density function. the output power level is ramped-up smoothly [3]. The reason for a gradual increase in the power level is to ensure that power is not spread to transmitter adjacent frequency channels. Fig. 1 shows amplitude and phase profiles of a received Wi-Fi turn-on transient. Following the channel noise, the received power level increases gradually after the transmitter is turned on. The transient starting point as estimated by a step change detector and the Wi-Fi actual transient starting points are marked on the Figure. As the step 2.412 GHz data acquisition change detector lags behind the actual starting point, phase characteristics and control important for classification are lost. Watkins Johnson IF out Tektronix Ethernet receiver TDS3054 WJ-8633 160 MHz digital scope Fig. 2 Experimental setup for data collection Experimental study: A transient capture system, shown in Fig. 2, was designed to analyse 802.11b Wi-Fi signals in the 2.4 GHz ISM band. Wi-Fi cards were installed in computers and set to ad hoc networking mode on radio channel 1 at 2.412 GHz. Wi-Fi radios transmit packets at regular intervals to announce their presence to the other devices that are listening on the same radio frequency. A Watkins Johnson model WJ-8633 receiver was tuned to Wi-Fi channel 1 and connected to an omnidirectional antenna for the reception of burst transmissions. The WJ-8633 is a VXI bus receiver controlled by a personal computer. The IF output of the WJ-8633 at 160 MHz was connected to a Tektronix Fig. 1 Example of 802.11b transmission data showing channel noise and TDS3054B 5 GS=s digital oscilloscope which has an Ethernet interface turn-on envelope and phase of transient waveform for control and data acquisition=transfer functions. An oscilloscope control program was written for a personal computer to collect tran- In this Letter, a modification to the step change detection scheme is sients from the Wi-Fi transmitters. Signals were sampled at a rate of proposed for transmitters that increase their transmit power gradually, 5GS=s with 9 bit resolution. One hundred transmissions were collected such as Wi-Fi radios. Transient detection is achieved using a Bayesian from nine different Wi-Fi radios. The in-phase and quadrature compo- ramp change detector that estimates the time instant where the signal nents of the sampled signals were obtained using a Hilbert transforma- power starts to increase gradually. The proposed technique is verified tionfollowedbydown-conversiontobase-bandinsoftware. ELECTRONICS LETTERS 17th March 2005 Vol. 41 No. 6 From the captured signal, the transmission starting point was Conclusions: In this Letter, a Bayesian ramp change detector is determined visually by an observer utilising both the amplitude and proposed for the detection of the turn-on transients of the Wi-Fi phase characteristics of the captured signals. The starting point of each radios. By comparison, a Bayesian step change detector, which is captured signal was then estimated using the Bayesian ramp change suitable for other applications, lags behind the transient turn-on method given by (3) and (4). The detection error was calculated as the starting point and has a standard deviation of the detection error difference between the actual observed values and the estimated values. that is three times higher than that of the ramp detector. This makes The histogram of the detection error is plotted in Fig. 3. The mean and the Bayesian ramp detector a better candidate as a turn-on transient the standard deviation of the error were calculated as 20 and 28 detector for Wi-Fi radios. samples, respectively. In this work, a signal model assuming a linear power increase at the turn-on is used. Although a raised cosine or an exponential increase 350 ramp would be a more accurate model for the transmit power shaping, the use step of a linear ramp model allows an analytical solution within the Bayesian 300 framework with acceptable error performance. The same technique can 250 also be used in detecting the turn-on transients of BlueTooth radios where the signal is shaped using a Gaussian window. 200 In a future study, a complete classification system will be imple- mented and the effect of the detection algorithm on the classification 150 rate will be investigated. number of occurences number 100 Acknowledgment: The work described herein was supported by the 50 Industry Canada Spectrum Engineering Branch. 0 -200 -100 0 100 200 300 400 500 error, samples # IEE 2005 8 November 2004 Electronics Letters online no: 20057769 Fig. 3 Histograms showing detection error for two different methods doi: 10.1049/el:20057769 compared to visual identification of start of transient O. Ureten and N. Serinken (Communications Research Centre, P.O. Box 11490 Station ‘H’ Ottawa, ON, Canada K2H 8S2) To compare the performance of the proposed ramp change detector to a step change detector, a signal model containing a step change was E-mail: [email protected] used: References m1 þ ui if 1 i < m di ¼ ð5Þ 1 Ureten, O., and Serinken, N.: ‘Detection, characterisation and m2 þ ui if m i N classification of radio transmitter turn-on transient signals’.
Load more

Recommended publications
  • Radar Transmitter/Receiver
    Introduction to Radar Systems Radar Transmitter/Receiver Radar_TxRxCourse MIT Lincoln Laboratory PPhu 061902 -1 Disclaimer of Endorsement and Liability • The video courseware and accompanying viewgraphs presented on this server were prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor the Massachusetts Institute of Technology and its Lincoln Laboratory, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, products, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government, any agency thereof, or any of their contractors or subcontractors or the Massachusetts Institute of Technology and its Lincoln Laboratory. • The views and opinions expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof or any of their contractors or subcontractors Radar_TxRxCourse MIT Lincoln Laboratory PPhu 061802 -2 Outline • Introduction • Radar Transmitter • Radar Waveform Generator and Receiver • Radar Transmitter/Receiver Architecture
    [Show full text]
  • History of Radio Broadcasting in Montana
    University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 1963 History of radio broadcasting in Montana Ron P. Richards The University of Montana Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y Recommended Citation Richards, Ron P., "History of radio broadcasting in Montana" (1963). Graduate Student Theses, Dissertations, & Professional Papers. 5869. https://scholarworks.umt.edu/etd/5869 This Thesis is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. THE HISTORY OF RADIO BROADCASTING IN MONTANA ty RON P. RICHARDS B. A. in Journalism Montana State University, 1959 Presented in partial fulfillment of the requirements for the degree of Master of Arts in Journalism MONTANA STATE UNIVERSITY 1963 Approved by: Chairman, Board of Examiners Dean, Graduate School Date Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number; EP36670 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. UMT Oiuartation PVUithing UMI EP36670 Published by ProQuest LLC (2013).
    [Show full text]
  • Electromagnetic Theory
    Electromagnetic Theory Electromagnetic Waves come in many varieties, What difference did it make? Maxwell’s new law including radio waves, from the ‘long-wave’ band and Faraday’s law give a wave equation, implying through VHF, UHF and beyond; microwaves; infrared, that any disturbance in the electric and magnetic visible and ultraviolet light; X-rays, gamma rays etc. fields will be self sustaining and travel out in space at the speed of light as an ‘electro-magnetic’ wave. About 1860, James Clerk Maxwell brought together all the known laws of electricity and What happened next? In 1887 Heinrich Hertz used magnetism: a spark-gap transmitter and receiver to demonstrate that these waves actually existed: • Gauss’ law gives the electric field pro- ∇∙D = ρ duced by electric charges • Faraday’s law gives the electric field produced by a changing magnetic field ∇×E = −∂B/∂t • Ampère’s law gave the magnetic field produced by an electric current ∇×H = J • A fourth law states that individual magnetic charges cannot exist ∇∙B = 0 In a metal wire electric charges flow round as a continuous current, while in an insulator they are only displaced by a small distance. Maxwell reasoned that this displacement could still make a current, ∂D/∂t, and so he reformulated Ampère’s law as ∇ ∇×H = J + ∂D/∂t. The spark generator causes a current spike across the gap in the central antenna. The transient pulse of electric field travels outwards at the speed of light. It alternates in direction (red for up, blue for down) making a Maxwell’s equations are essential to the wave, and carries with it a magnetic field and electromagnetic energy.
    [Show full text]
  • Digital Microwave Link
    DIGITAL MICROWAVE LINK INTREPID™ MicroWave 330 is a volumetric perimeter detection system for fencelines, open areas, gates, entryways, walls and rooftop applica- KEY FEATURES tions. Based on Southwest Microwave’s field-proven microwave detection technology, advanced Digital Signal Processing (DSP) discriminates be- RANGE: 457 M (1500 FT) tween intrusion attempts and environmental disturbances, mitigating risk of site compromise while preventing nuisance alarms. The system’s poll- SINGLE PLATFORM NETWORKING ing capabilities enable continuous monitoring of alarm and tamper status. DIGITAL SIGNAL PROCESSING FOR MicroWave 330 operates at K-band frequency, achieving superior per- HIGH PD / LOW NAR formance to X-band sensors. Because K-band is 2.5 times higher than X-band, the multipath signal generated by an intruder is more focused, FRESNEL SUPPRESSION ALGORITHMS and detection of stealthy intruders is correspondingly better. K-band fre- REDUCE OUTER FIELD DISTURBANCES quency also limits susceptibility to outside interference from air/seaport radar or other microwave systems. SOFTWARE-CONTROLLED SETUP BUILT-IN SYNCHRONIZATION PREVENTS Antenna beam width is approximately 3.5 degrees in the horizontal and vertical planes. A true parabolic antenna assures long range operation, INTERFERENCE BETWEEN SENSORS superior beam control and predictable Fresnel zones. Advanced receiver TETHERED MODE FOR OPTIMAL design increases detection probability by alarming on partial or complete beam interruption, increase / decrease in signal level or jamming by SENSOR CONTROL AND INTERFERENCE other transmitters. RESISTANCE MicroWave 330’s Tethered mode of operation optimizes sensor con- trol. Its on-board synchronization circuitry eliminates external interfer- ence and allows multiple MicroWave 330’s and Southwest Microwave transceivers to operate without mutual interference.
    [Show full text]
  • Recommendations for Transmitter Site Preparation
    RECOMMENDATIONS FOR TRANSMITTER SITE PREPARATION IS04011 Original Issue.................... 01 July 1998 Issue 2 ..............................11 May 2001 Issue 3 ................... 22 September 2004 Nautel Limited 10089 Peggy's Cove Road, Hackett's Cove, NS, Canada B3Z 3J4 T.+1.902.823.2233 F.+1.902.823.3183 [email protected] U.S. customers please contact: Nautel Maine, Inc. 201 Target Industrial Circle, Bangor ME 04401 T.+1.207.947.8200 F.+1.207.947.3693 [email protected] e-mail: [email protected] www.nautel.com Copyright 2003 NAUTEL. All rights reserved. THE INFORMATION PRESENTED IN THIS DOCUMENT IS BELIEVED TO BE ACCURATE AND RELIABLE. IT IS INTENDED TO AUGMENT COMPETENT SITE ENGINEERING. IF THERE IS A CONFLICT BETWEEN THE RECOMMENDATIONS OF THIS DOCUMENT AND LOCAL ELECTRICAL CODES, THE REQUIREMENTS OF THE LOCAL ELECTRICAL CODE SHALL HAVE PRECEDENCE. Table of Contents 1 INTRODUCTION 1.1 Potential Threats 1.2 Advantages 2 LIGHTNING THREATS 2.1 Air Spark Gap 2.2 Ground Rods 2.2.1 Ground Rod Depth 2.3 Static Drain Choke 2.4 Static Drain Resistors 2.5 Series Capacitors 2.6 Single Point Ground 2.7 Diversion of Transients on RF Feed Coaxial Cable 2.8 Diversion/Suppression of Transients on AC Power Wiring 2.9 Shielded Isolation Transformer 3 ELECTROMAGNETIC SUSCEPTIBILITY 3.1 Shielded Building 3.2 Routing of RF Feed Coaxial Cable 3.3 Ferrites for Rejection of Common Mode Signals 3.4 EMI Filters 3.5 AC Power Sources Not Recommended for Use 4 HIGH VOLTAGE BREAKDOWN CONCERNS 4.1 RF Transmission Systems 4.2 High Voltage Feed Throughs 4.2.1 Insulator
    [Show full text]
  • Amplitude Modulation Fundamentals
    chapter 3 Amplitude Modulation Fundamentals In the modulation process, the baseband voice, video, or digital signal modifies another, higher-frequency signal called the carrier, which is usually a sine wave. Carrier A sine wave carrier can be modified by the intelligence signal through ampli- tude modulation, frequency modulation, or phase modulation. The focus of this chapter is amplitude modulation (AM). Amplitude modulation (AM) Objectives After completing this chapter, you will be able to: Calculate the modulation index and percentage of modulation of an AM signal, given the amplitudes of the carrier and modulating signals. Define overmodulation and explain how to alleviate its effects. Explain how the power in an AM signal is distributed between the carrier and the sideband, and then compute the carrier and sideband powers, given the percentage of modulation. Compute sideband frequencies, given carrier and modulating signal frequencies. Compare time-domain, frequency-domain, and phasor representations of an AM signal. Explain what is meant by the terms DSB and SSB and state the main advantages of an SSB signal over a conventional AM signal. Calculate peak envelope power (PEP), given signal voltages and load impedances. 93 3-1 AM Concepts As the name suggests, in AM, the information signal varies the amplitude of the carrier sine wave. The instantaneous value of the carrier amplitude changes in accordance with the amplitude and frequency variations of the modulating signal. Figure 3-1 shows a single- frequency sine wave intelligence signal modulating a higher-frequency carrier. The carrier frequency remains constant during the modulation process, but its amplitude varies in accordance with the modulating signal.
    [Show full text]
  • A Short History of Radio
    Winter 2003-2004 AA ShortShort HistoryHistory ofof RadioRadio With an Inside Focus on Mobile Radio PIONEERS OF RADIO If success has many fathers, then radio • Edwin Armstrong—this WWI Army officer, Columbia is one of the world’s greatest University engineering professor, and creator of FM radio successes. Perhaps one simple way to sort out this invented the regenerative circuit, the first amplifying re- multiple parentage is to place those who have been ceiver and reliable continuous-wave transmitter; and the given credit for “fathering” superheterodyne circuit, a means of receiving, converting radio into groups. and amplifying weak, high-frequency electromagnetic waves. His inventions are considered by many to provide the foundation for cellular The Scientists: phones. • Henirich Hertz—this Clockwise from German physicist, who died of blood poisoning at bottom-Ernst age 37, was the first to Alexanderson prove that you could (1878-1975), transmit and receive Reginald Fessin- electric waves wirelessly. den (1866-1932), Although Hertz originally Heinrich Hertz thought his work had no (1857-1894), practical use, today it is Edwin Armstrong recognized as the fundamental (1890-1954), Lee building block of radio and every DeForest (1873- frequency measurement is named 1961), and Nikola after him (the Hertz). Tesla (1856-1943). • Nikola Tesla—was a Serbian- Center color American inventor who discovered photo is Gug- the basis for most alternating-current lielmo Marconi machinery. In 1884, a year after (1874-1937). coming to the United States he sold The Businessmen: the patent rights for his system of alternating- current dynamos, transformers, and motors to George • Guglielmo Marconi—this Italian crea- Westinghouse.
    [Show full text]
  • Licensed Devices General Technical Requirements
    Licensed Devices General Technical Requirements (Detailed Update October 2005) Steven Dayhoff Federal Communications Commission Office of Engineering & Technology October, 2005 ¾TCB Workshop 1 Sessions for licensed devices intended to give an overview of FCC Processes & Rules, not to show limits for every type of device. The information covered is mainly related to equipment authorization of the transmitting equipment and not the licensing of the station. 1 Overview General Information How to find information at the FCC Creating a Grant Organizing a Report Licensed Device Checklist October, 2005 ¾TCB Workshop 2 This session will cover general information related to the FCC rules and technical requirements for licensed devices. Assumption is that everyone is familiar with testing equipment so test setup and equipment settings will not covered. The approval process for these types of equipment was previously called Type Acceptance or Notification. Now all methods of equipment approval are called Certification. This information generally applies to all Radio Service Rules for scopes B1 through B4. 2 General Information Understanding how FCC rules for licensed equipment are written and how FCC operates The FCC rules are Title 47 of the Code of Federal Regulations Part 2 of the FCC Rules covers general regulations & Filing procedures which apply to all other rule parts Technical standards for licensed equipment are found in the various radio service rule parts (e.g. Part 22, Part 24, Part 25, Part 80, and Part 90, etc.) All material covered in this training is either in these rules or based on these rules October, 2005 ¾TCB Workshop 3 There are about 15 different radio service rule Parts which require equipment to be authorized before an operators license can be obtained.
    [Show full text]
  • Amplitude Modulation Transmitter Design
    Amplitude LAB Modulation 5 Transmitter Design Introduction The motivation behind this project is to design, implement, and test an Amplitude Modulation (AM) Transmitter. The Transmitter consists of a Balanced Modulator circuit which takes an audio signal stream from a Walkman and mixes it with a sinusoidal signal from a 1MHz oscillator. The resulting output is amplified by an output stage before being transmitted through a wire-antenna. AM Transmitter Floorplan: Design Goals Given the limited timeframe, we are providing you with the individual circuits that you need to design and construct. Fig. 1 shows the floorplan for the AM Transmitter. It consists of a Balanced Modulator which multiplies an audio fre- quency (20Hz to ~15kHz) signal with a 1MHz carrier frequency sinusoidal signal. The Balanced Modulator’s output is amplified by an output stage which drives an antenna (in this experiment, the antenna is just a 3” copper wire). The Balanced Modulator (Fig. 2) is essentially an analog multiplier: its time domain output signal, Vout(t) is linearly related to the product of the time domain input signals V1(t) (called the modulation signal) and V2(t) (called the carrier sig- nal). Its transfer function has the form: V ()t = k ⋅⋅V ()t V ()t out 1 2 The Balanced Modulator uses the principle of the dependence of the BJT’s transconductance, gm, on the emitter current bias. In order to demonstrate the principle, consider the load currents IL1 and IL2. From your knowledge of differ- ential amplifier operation, IL1 V1 I – I = g ⋅ V ≈ -------- ⋅ ------ L1 L2 m in VT 2 Also, the bias current IB in the differential amplifiers can be expressed as: V – 0.7 ≈ 2 IB ------------------ RE 1 Lab : Amplitude Modulation Transmitter Design Antenna Balanced O/P stage Walkman Modulator Amplifier 1MHz Oscillator Figure 1 — Amplitude Modulation Transmitter floorplan.
    [Show full text]
  • Rosemount™ 3051 Wireless Pressure Transmitters Pressure, Level, and Flow Solutions with Wirelesshart® Protocol
    Reference Manual 00809-0100-4100, Rev. BA May 2017 Rosemount™ 3051 Wireless Pressure Transmitters Pressure, Level, and Flow Solutions with WirelessHART® Protocol Reference Manual Contents 00809-0100-4100, Rev. BA May 2017 Contents 1Section 1: Introduction 1.1 Using this manual . 1 1.2 Models covered . 1 1.3 Product recycling/disposal. 1 2Section 2: Configuration 2.1 Overview . 3 2.2 Safety messages. 3 2.3 Required bench top configuration . 4 2.3.1 Connection diagrams . 5 2.4 Basic setup . 5 2.4.1 Set device tag . 5 2.4.2 Join device to network. 6 2.4.3 Configure update rate . 6 2.4.4 Set process variable units . 6 2.4.5 Remove power module . 7 2.5 Configure for pressure . 7 2.5.1 Re-mapping device variables . 7 2.5.2 Set range points . 8 2.5.3 Set transmitter percent of range (transfer function) . 8 2.6 Configure for level and flow. 9 2.6.1 Configuring scaled variable . 9 2.6.2 Re-mapping device variables . 11 2.6.3 Set range points . 12 2.7 Review configuration data . 13 2.7.1 Review pressure information . 13 2.7.2 Review device information . 13 2.7.3 Review radio information . 14 2.7.4 Review operating parameters . 14 2.8 Configuring the LCD display . 15 2.9 Detailed transmitter setup. 15 2.9.1 Configure process alerts . 15 2.9.2 Damping . 16 2.9.3 Write protect. 16 2.10 Diagnostics and service. 17 2.10.1 Master reset . 17 Contents iii Contents Reference Manual May 2017 00809-0100-4100, Rev.
    [Show full text]
  • Transmitter and Receiver Systems
    Telemetry Standard RCC Document 106-07, Chapter 2, September 2007 CHAPTER 2 TRANSMITTER AND RECEIVER SYSTEMS Paragraph Subject Page 2.1 Radio Frequency Standards for Telemetry ..................................................... 2-1 2.2 Definitions ...................................................................................................... 2-1 2.3 UHF Bands ..................................................................................................... 2-2 2.4 UHF Telemetry Transmitter Systems ............................................................. 2-4 2.5 UHF Telemetry Receiver Systems ............................................................... 2-15 REFERENCES LIST OF FIGURES Figure 2-1. FQPSK-JR baseband signal generator............................................................. 2-6 Figure 2-2. Basic SOQPSK. ............................................................................................... 2-8 Figure 2-3. SOQPSK transmitter...................................................................................... 2-10 Figure 2-4. Conceptual CPM modulator. ......................................................................... 2-11 Figure 2-5. Continuous single sideband phase noise power spectral density................... 2-13 LIST OF TABLES Table 2-1. Telemetry Frequency Allocations.................................................................... 2-2 Table 2-2. FQPSK-JR Shaping Filter Definition .............................................................. 2-7 Table 2-3. FQPSK-B and FQPSK-JR
    [Show full text]
  • Am Radio Transmission
    AM RADIO TRANSMISSION 6.101 Final Project TIMI OMTUNDE SPRING 2020 AM Radio Transmission 6.101 Final Project Table of Contents 1. Abstract 2. Introduction 3. Goals a. Base b. Expected c. Stretch 4. Block Diagram 5. Schematic 6. PCB Layout 7. Design and Overview 8. Subsystem Overview a. Transmitter i. Oscillator ii. Modulator iii. RF Amplifier iv. Antenna b. Receiver c. Battery Charger 9. Testing and Debugging 10. Challenges and Improvements 11. Conclusion 12. Acknowledgments 13. Appendix Omotunde 1 AM Radio Transmission 6.101 Final Project AM Radio Transmission Abstract Amplitude modulation (AM) radio transmissions are commonly used in commercial and private applications, where the aim is to broadcast to an audience - communications of any type, whether it be someone speaking, Morse code, or even ambient noise. In AM radio frequencies (RF) transmissions, the amplitude of the wave is modulated and encoded with the transmitted sound, while the frequency is kept the same. Furthermore, AM radio transmissions can occur on different frequencies, with broadcasts of the same frequency interfering with each other. Therefore, it is important to select a unique – or as unique as possible – frequency band in order to transmit clean, interference free, communications. And currently, many 1-way and 2-way radios, with transmission ability have some digital component in order to improve different aspects of the radio. Thus, for my 6.101 final project, I have built a fully analog circuit, in keeping with the theme of the class, that can be used to broadcast to specific AM frequencies. Thus, the goal is to broadcast as far as possible while minimizing the power consumed.
    [Show full text]