Phase-ambiguity resolution for QPSK modulation systems.

Cover of: Phase-ambiguity resolution for QPSK modulation systems. |

Published by National Aeronautics and Space Administration, Jet Propulsion Laboratory, California Institute of Technology in Pasadena, Calif .

Written in English

Read online

Subjects:

  • Modulation (Electronics)

Edition Notes

Book details

Other titlesPhase ambiguity resolution for QPSK modulation systems.
StatementTien Manh Nguyen.
SeriesJPL publication -- 89-4., NASA-CR -- 185385., NASA contractor report -- NASA CR-185385., JPL publication -- 89-4.
ContributionsJet Propulsion Laboratory (U.S.)
The Physical Object
FormatMicroform
Pagination1 v .
ID Numbers
Open LibraryOL15290277M

Download Phase-ambiguity resolution for QPSK modulation systems.

The item Phase-ambiguity resolution for QPSK modulation systems, Part II, A method to resolve the phase-ambiguity for the offset QPSK modulation systems, Tien Manh Nguyen represents a specific, individual, material embodiment of a distinct intellectual or artistic creation found in Indiana State Library.

Phase-Ambiguity Resolution for QPSK Modulation Systems Part II: A Method to Resolve the Phase-Ambiguity for Offset QPSK Modulation Systems Tien Manh Nguyen May 15, NASA National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena.

California. Part 1 reviews the current phase-ambiguity resolution techniques for QPSK coherent modulation systems. Here, those known and published methods of resolving phase ambiguity for QPSK with and without Forward-Error-Correcting (FEC) are discussed.

The necessary background is provided for a complete understanding of the second part where a new technique will be discussed. An appropriate Cited by: 1.

Abstract Part 2 presents a new method to resolve the phase-ambiguity for Offset QPSK modulation systems. When an Offset Quaternary Phase-Shift-Keyed (OQPSK) communications link Author: Tien M.

Nguyen. Get this from a library. Phase-ambiguity resolution for QPSK modulation systems. Part 1, A review. [Tien Manh Nguyen; Jet Propulsion Laboratory (U.S.)].

Abstract The use of Digital Techniques in satellite communications has generated considerable interest in developing and implementing modulation techniques which are efficient both in terms of bandwidth and power utilization - such as Binary Phase Shift Keyed Systems (BPSK) and Quadrature Phase Shift Keyed Systems (QPSK).

A demodulator for OQPSK signals modulated with two unique words resolves eight possible cominbations of phase ambiguity which may product data error by first Cited by: Phase ambiguity resolution for offset QPSK modulation systems: Authors: Nguyen, Tien M.

Origin: STI: NASA/STI Keywords: Ambiguity, Demodulation, Digital Techniques, Phase Lock Demodulators, Phase Shift Keying, Resolution, Signal Processing, Coding, Decoding, Patents, Synchronism and then the remaining four using a phase ambiguity.

Jun 18,  · Although the unique-word detection technique for phase-ambiguity resolution in a QPSK communication system has been known, as noted in the above discussion of background art, its role in the present invention is unique, and so the block diagram of FIG. 3 is unique. Get this from a library.

Phase-ambiguity resolution for QPSK modulation systems. Part II, A method to resolve the phase-ambiguity for the offset QPSK modulation systems. [Tien Manh Nguyen; Jet Propulsion Laboratory (U.S.)]. emphasize new phase-ambiguity resolution techniques for the coherent QPSK systems.

COHERENT QPSK MODULATION SYSTEM Before going into details of the current available phase- ambiguity resolution techniques, it is essential to describe the basic structure of a coherent QPSK modulation system. Depicted. This book describes the advances and applications in Sliding mode control (SMC) which is widely used as a powerful method to tackle uncertain nonlinear systems.

The book is organized into In QPSK systems, phase ambiguity occurs at any multiple of 90 degrees. This is to say that when the PLL “locks” onto the signal at the receiver, the symbol previously located in the first quadrant at the transmitter may now be located in a different quadrant at the receiver.

The Carrier Synchronizer block may lock to the unmodulated carrier with a phase shift of 0, 90,or degrees, which can cause a phase ambiguity.

For details of phase ambiguity and its resolution, please refer to Chapter and in [ 1]. The Phase Offset Estimator subsystem determines this. Phase ambiguity resolution for offset QPSK modulation systems.

By Tien M. Nguyen. and then the remaining four using a phase ambiguity resolver which detects the words to not only reverse the received I(sub R) and Q(sub R) data channels, but to also invert (complement) the I(sub R) and/or Q(sub R) data, or to at least complement the I(sub R Author: Tien M.

Nguyen. For other exploration options, refer to the QPSK Transmitter and Receiver example using Simulink. Summary. This example simulates digital communication over an AWGN channel. It shows how to model several parts of the QPSK system such as modulation, frequency and phase recovery, timing recovery, and frame synchronization.

Efficient QPSK Burst Demodulator for Onboard Application phase ambiguity resolution and burst time synchronization. Thus, after the preamble and UW segments have been Modulation QPSK ½ FEC Mode Burst Phase ambiguity resolution By differential encoding and decoding.

Jun 17,  · There is a performance penalty for using differential encoding, so if you're tight on link budget you need to resolve the phase ambiguity somehow (and there are lots of ways to do it, but they all have some sort of tradeoff). The same problem occurs for any symmetric constellation, e.g., BPSK, QPSK, 8PSK, M-ary QAM, M-ary APSK, etc., etc.

Part 1 reviews the current phase-ambiguity resolution techniques for QPSK coherent modulation systems. Here, those known and published methods of resolving phase ambiguity for QPSK with and without Forward-Error-Correcting (FEC) are wrcch2016.com: Tien Manh Nguyen.

EPA3 - Method for phase ambiguity resolution in a trellis coded modulation system - Google Patents Method for phase ambiguity resolution in a trellis coded modulation system A method of supporting single synchronization on the support of a dispersed-energy QPSK signal: DEC1 (en) * Cited by: 2.

Illustrate the use of key Communications Toolbox™ System objects for QPSK system design. In this example, which is not a function of the QPSK modulation.

Then it performs an FFT on the modulation-independent signal to estimate the tone at four times the frequency offset. phase ambiguity resolution, demodulation and text message decoding.

Jan 20,  · The complete waveform simulation for the aforementioned QPSK modulation and demodulation is given next. The simulation involves, generating random message bits, modulating them using QPSK modulation, addition of AWGN channel noise corresponding to the given signal-to-noise ratio and demodulating the noisy signal using a coherent QPSK receiver.

The wrcch2016.comrSynchronizer System object compensates for carrier frequency and phase offsets in signals that use single-carrier modulation schemes. The Examples demonstrate carrier synchronization and resolution of phase ambiguity.

('Modulation','QPSK') creates a carrier synchronizer System object to use with a QPSK modulated wrcch2016.com: Create duplicate System, object.

Lecture 12 Carrier Phase Synchronization. 2 for QPSK. 10 EE/EE Digital Communications Suketu Naik Carrier Phase Synchronization for QPSK Phase Ambiguity Resolution: Unique Word.

19 EE/EE Digital Communications Suketu Naik How to resolve the phase ambiguity?: Commonly used in wired and wireless. QPSK MODULATION AND DEMODULATION QPSK Modulation: In digital modulation techniques a set of basis functions are chosen for a particular modulation wrcch2016.comlly the basis functions are orthogonal to each other.

Basis functions can be derived using ‘Gram Schmidt orthogonalization’ wrcch2016.com the basis function are chosen. Figure 2: Coherent detection of differentially encoded BPSK signal.

Following is the Matlab implementation of the waveform simulation model for the method discussed above. Both the differential encoding and differential decoding blocks, illustrated in Figures 1 and 2, are linear time-invariant filters.

Message from the Technical Program Chair. Phase-ambiguity resolution for QPSK modulation systems. Part 1: A review Part 1 reviews the current phase-ambiguity resolution techniques for QPSK.

Phase-shift keying (PSK) is a digital modulation process which conveys data by changing (modulating) the phase of a constant frequency reference signal (the carrier wave).The modulation is accomplished by varying the sine and cosine inputs at a precise time.

It is widely used for wireless LANs, RFID and Bluetooth communication. Any digital modulation scheme uses a finite number of distinct. 5) Data decoder: Uses a Barker code to perform frame synchronization, phase ambiguity resolution, and demodulation.

Also, the data decoder compares the regenerated message with the transmitted message and calculates the BER.

For more information about the system components, refer to the QPSK Receiver with USRP® Hardware example using Simulink.

Note that the output of the Symbol Synchronizer contains one sample per symbol. At this stage, the constellation truly resembles a QPSK signal. The few symbols that gradually move away from the origin correspond to the frame start and end.

Preamble Detection, Despreading and Phase Ambiguity Resolution. QPSK Receiver Using Analog Devices AD/AD Illustrate the use of key Communications Toolbox™ System objects for QPSK system design.

The Data Decoding subsystem performs frame synchronization, phase ambiguity resolution, demodulation and text message decoding. The HDL Optimized QPSK Receiver with Captured Data example provides a hardware-friendly solution that performs baseband processing to handle a time-varying frequency offset and a time-varying symbol delay.

Specifically, this example provides an HDL-optimized reference design of a practical digital receiver to mitigate the above-mentioned. QPSK modulation QPSK Signal mode continuous signal Symbol rate Kbps to 2 Mbps FEC decoding mode Viterbi decoding Phase ambiguity resolution method by different encoding and de-coding methods Judgment Type 3-bit soft decision 3.

PROPOSED DESIGN OF THE DEMODULA- The Open Automation and Control Systems Journal,Volume 6 Xiquan. Part 2 presents a new method to resolve the phase-ambiguity for Offset QPSK modulation systems.

When an Offset Quaternary Phase-Shift-Keyed (OQPSK) communications link is utilized, the phase ambiguity of the reference carrier must be resolved. At the transmitter, two different unique words are separately modulated onto the quadrature carriers.

Streaming Input and Output: The HDL optimized QPSK receiver processes data one sample at a time. The captured real-world signal is streamed into the receiver front-end. The streaming output of the HDL optimized receiver is buffered and passed to the text message decoder.

The example of a hand made QPSK modulator/demodulator is used to illustrate this approach. 2 Digital modulation backgrounds. At the beginning of the practical lesson, we first extract from the theory, the fundamental definitions of digital modulation [1].

Since the in-phase and quadrature component are orthogonal we can superimpose two BPSK signals with a 90° phase shift and arrive at four constellation points. This format is called quadrature phase shift keying (QPSK) and carries two bits per symbol (and per polarization), i.e., each constellation point represents a combination of two bits.

All About Modulation - Part I Basic Concepts, Signal Space, Constellations and Phase Shift Keying modulations (PSK, QPSK, OQPSK, M-PSK, π/4-QPSK, MSK, and GMSK) Basic Concepts of modulation Three kinds of modulations Modulation is the process of facilitating the transfer of information over a medium.

Voice can not be sent be very far by screaming. % stripping, frame synchronization, carrier phase ambiguity resolution, and % message decoding. % % In this example, the SDRuReceiver System object receives data % corrupted by the transmission over the air and outputs complex baseband % signals which are processed by the QPSK Receiver System.

Nov 11,  · The differential decoder is often implemented as part of the demodulator so that the bits that the Viterbi decoder works on have no phase ambiguity in them.

Also, in QPSK systems, the phase ambiguity is not just an interchange of 00 11 etc but a rotation of pi/2, pi, or 3pi/2, and so life is more complicated than you have indicated. A Satellite Telemetry Transmitting System with Pre-Modulation Filtering By D.V.

Ramana, R. Jolie, V.S. Rao and S. Pal The new QPSK data transmission system at C-band Sasikumar wrcch2016.com, “Phase ambiguity resolution in QPSK communication systems.QPSK systems is that of phase ambiguity at the re- Ambiguity Resolution in a Four-Phase PSK Communi- ery circuit to distinguish the reference phase from the unique words (sync words) separately modulated onto other phase (or phases) of the received carrier.

For the two quadrature 1 and Q channels at the transmitter.Ambiguity resolution finds true range and true speed by using ambiguous range and ambiguous speed measurements with multiple PRF.

Doppler Measurements. Doppler systems involve velocity measurements similar to the kind of measurements made using a strobe light.

38775 views Friday, November 27, 2020