Top PDF Automated RF Over Fiber Signal Measurement System

Automated RF Over Fiber Signal Measurement System

Automated RF Over Fiber Signal Measurement System

The fiber optical is one major discovery in the human history. When people moved from wired to wireless, they had the freedom hassle-free communication, but they had to pay a price. The system became complex and costlier to build and deploy. As everyone know a message signal needs a carrier to send and has the frequency of the carrier increases the noise in the transmission decrease. The wireless system got up Ghz and it’s hard for generating such carrier. To overcome all these problems and to increases the speed of the communication, Researchers have used light has carrier to send message. The system was developed to send o’s and 1’s or commonly known has digital communication. As ages pasted, there was many improvements in the system but still used digital technology. The concept of RF (Sine –wave) over fiber was introduced and many researchers have showed ways, How the fiber can be used in modifying RF signals. This is new concept and there are only few measurement techniques to qualify the system.
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Advantages and Limitation of Radio over Fiber System

Advantages and Limitation of Radio over Fiber System

(v) Dual Mode Lasers: As stated earlier the major drawback of optical heterodyning-based techniques is the sensitivity to phase noise of the two heterodyning signals, and the dependence of the RF beat signal on the polarization state difference of the two heterodyning carriers. Several techniques used to improve beat signal phase noise have been described. A dual mode laser designed to test the viability of this technique showed that direct electrical injection at a sub-harmonic of the beat frequency was still needed in order to generate a pure mm-wave. The main advantage of the DML approach is that it does not require complex feedback circuitry as does the different optical injection locking methods discussed above. However, the method has limitations regarding tenability, because of its narrow locking range.
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Rotation Measurement and Signal Processing For Navigation Control System Using Fiber Optic Gyroscope

Rotation Measurement and Signal Processing For Navigation Control System Using Fiber Optic Gyroscope

The main functions of the Navigation signal measurement and Signal Processing Unit are:Extraction of rotation rate information (Sagnac Phase) from the Sensor outputs and computation of incremental angles.Compensation of the sensor outputs over operating temperature range.A rotation rate sensor based on Sagnac effect is used. In this sensor, the photo detector output measured at the phase modulation frequency is used as an error signal. The Signal Processing Unit accepts this error signal as input. The unit has a feedback loop which introduces a controlled amount of non- reciprocal phase difference to counteract the Sagnac Phase shift. Thus the net phase difference is maintained at zero.
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Analysis of CNR Penalty in Radio over Fiber System Including the Effect of Phase Noise & RF Oscillator

Analysis of CNR Penalty in Radio over Fiber System Including the Effect of Phase Noise & RF Oscillator

Radio over fiber system is that where light is modulated by a radio signal and transmitted over an optical link. As shown in fig.2 The output signal of the MZM is transmitted by a standard SMF and detected by a photodiode (PD) to generate the photocurrent i(t) at a Base station. The wireless channel makes the signals at its amplitude and phase distortion. MS amplifies and filters the received signal to detect the transmitted RF signal. LD [6] with an DEMZM (Dual Electrode Mach Zehnder Modulator) [18] in a central CS. Here RF signal from an oscillator is split by both power splitter & a 90 o phase shifter. Now this RF signal is optically modulated by the LD with an MZM. This optically modulated signal is transmitted to the PD & the photocurrent i(t) across to the transmitted RF signal is carried out by the filter. At the result, Data are extracted through RF demodulation process at MS.
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FIBER OPTIC TRANSMITTERS, RECEIVERS, TRANSCEIVERS AND SUBSYSTEMS FOR WIRELESS AND RF SIGNAL DISTRIBUTION

FIBER OPTIC TRANSMITTERS, RECEIVERS, TRANSCEIVERS AND SUBSYSTEMS FOR WIRELESS AND RF SIGNAL DISTRIBUTION

transceivers are rugged, compact OEM modules designed for easy integration into your commercial AMPS, GSM, PCS/PCN, M/LMDS, WLL, IF, satellite terminal or distinctive antenna system configuration. Fiber-Span is addressing public safety needs by providing fiber optic wireless solutions for police, fire, emergency, first responder and Homeland Security radio systems applications. Our solutions for Defense and Military organizations are also leading the way by providing reliable and secure communications links for ground, airborne, shipboard, radar, telemetry, GPS and intelligence solutions in the HF/UHF/VHF and microwave radio frequencies.
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Design and Performance Optimization of Bidirectional SCM based Radio over Fiber System

Design and Performance Optimization of Bidirectional SCM based Radio over Fiber System

The experimental setup of bidirectional radio over fiber system employing Amplitude Shift Keying modulation further incorporating dispersion compensation techniques are shown in fig.2, fig.3, fig.4, fig5. Downlink data signal generated by pseudorandom generator is mixed with local oscillator having frequency 10 GHZ and a carrier generator having number of RF carriers. For the generation of downstream signal, a series of continuous wave(CW) with various wavelengths are modulated by LiNbO3 Mach Zehnder modulator using non return to zero data stream data. The resultant signal is then transmitted over the fiber. Photodetector are used at the reception for the conversion of optical signal back to electrical signal. The transmission quality of the signal is analysed with the help of various analyzer like eye diagram analyzer, bit error rate analyzer.
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AUTOMATED WIRE LENGTH MEASUREMENT AND CUTTING SYSTEM

AUTOMATED WIRE LENGTH MEASUREMENT AND CUTTING SYSTEM

In 21 st century the electronics technology has raised at its glory. Comparing the initial technology and present technology there is vast development in field of electronics. In Industrial, 9electronics sector and household there is inherent need of electric wires. The types of wires vary from single strand wire to the optical fiber cables. The required wire may be in different size and different length. As per industrial demand, we have developed the system which automatically measures the length of the wire and cuts it as per specified length. This system can be easily handled by the subordinates and the unskilled persons in industry. The main components of the system are: Micro-controller, DC motors and cutting unit. Microcontroller is acting as a brain of our system [1]. In the proposed system rotating shaft of fiber DC motor is used for estimation of the length [2]. Subsequently the system uses softwares like Proteus, Keil µ vision, Flash Magic for microcontroller programming etc. GE-International Journal of Engineering Research
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Study on 4PAM Radio over Fiber  System Using Self Mixing Technique

Study on 4PAM Radio over Fiber System Using Self Mixing Technique

Figure 2 Illustrates the configuration of the proposed scheme. At the transmitter, light-wave source emitted from two external cavity lasers (ECL1 and ECL2) as the continuous wave (CW) laser, the frequency tone spac- ing of the two ECLs is 60 GHz. The maximum line width of the two CWs is 10 MHz and coupled together by a 3 dB optical coupler, where one (work frequency at 193.1 THz) is modulated intensity via a MZM driven with the 10 Gbit/s baseband 4 PAM signal and the other one (work frequency at 193.16 THz) without data modula- tion. The graph of time-domain and frequency-domain of the RF-4 PAM signal is presented in Figure 3(i) and Figure 3(ii), respectively. We can see that the main bandwidth of RF baseband is 5 GHz because all the power is concentrated in the innerbroad band of 5 GHz.
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SCADA Over Fiber Optic Communications System

SCADA Over Fiber Optic Communications System

The main results of the proposed system include the measurement optical power received at the detector, and calculating the signal to noise ratio at optical receiver then finding the BER according to the mentioned equations. The work includes usage of the optical fiber ten pieces each of 2km length. So, the total length will be 20 km.

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Optical millimeter wave signal generation with frequency 16-tupling using cascaded MZMs and no optical filtering for radio over fiber system

Optical millimeter wave signal generation with frequency 16-tupling using cascaded MZMs and no optical filtering for radio over fiber system

desired. It is important to note that the MZMs operate at maximum transmission point. The first MZM sup- presses all the odd harmonics present in the spectrum, leaving behind only the even harmonics in the spectrum. Before the first stage output is fed to the second MZM, the RF signal driving MZM2 is phase shifted by 45 de- grees. The phase shifted RF signal is fed as the input to the second and the third MZMs, which further suppress the even harmonics, leaving behind the 8th harmonic on each side. Proper and efficient adjustment of dc biasing ensures that all the harmonics are suppressed except for the 8th harmonic on either side. Upon the photo detec- tion, peak power is achieved in the 16th harmonics, while all the other harmonics are eliminated. The frequency of the input RF LO signal is 3.75 GHz,
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RF Based Complex Impedance Measurement

RF Based Complex Impedance Measurement

A variety of methods for impedance measurement exists [6]: bridge, resonant, I-V, RF I-V, network anlaysis. The bridge method exhibits high accuracy, but due to the need of balancing this method we consider not suitable for our application. Resonant method is achieving good for our application. Resonant method is achieving good accuracy in quality of inductance measurement, but there is a need for resonance tuning. It can be considered as an option for few measurements as it was done in [7], but it is suitable for low cost automated system. The data analysis indicates that I-V and auto balancing bridge methods look the most promising. We will concentrate on the auto balancing bridge method because of its good and accurate performance among high frequency and impedance ranges.
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Development of an Automated Measurement System for Checking Irradiation Non-uniformity of Solar Simulators

Development of an Automated Measurement System for Checking Irradiation Non-uniformity of Solar Simulators

The structure of the proposed automated measurement system is shown in Fig. 3, and serial peripheral interface (SPI) signal between the RF module and the Arduino Mega/UNO [10] is further shown in Fig. 4. The PV cell detects the irradiance on the irradiated surface of the measuring location of the solar module and its output voltage is sent to an analog input (AI) of Arduino Mega. The control signals from the PC include operation mode, i.e., automation mode and manual mode, position location, start/restart measurement, start transmission, DC motor control and stepping motor control, can be transmitted through the RF modules located on both the PC side and the robot side. In Fig. 1, two sets of DC motors including transmission gears are employed to drive four wheels for driving the robot to move along the horizontal direction, and the other two sets of DC motors including transmission gears are employed to drive four wheels for driving the robot to move along the vertical direction. Moreover, two sets of stepping motors including transmission mechanism are employed to control the mechanism which switches either horizontal moving drive wheel or vertical moving drive wheel to contact the floor. Fig. 5 reveals this switching effect. On the other side, the monitoring signal from Arduino Mega like irradiance data being acquired can be transmitted to the PC. Since the RF module only has SPI, the feedback data transmitted from Arduino can not be transferred to PC. An Arduino UNO is used to bridge the SPI of RF module and the USB of PC.
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Understanding Standard OFDM WiMAX
 Signal Access in Radio Over Fiber System

Understanding Standard OFDM WiMAX Signal Access in Radio Over Fiber System

Figure 1(a) shows the current WiMAX signal access network. In this system, each BS will provide certain cell coverage for the network. Besides, several BSs are connected to the access service network gateway (ASN-GW) for data communication and synchronization. However, the large numbers of BSs would increase the cost for WiMAX system. Because of this, a BS can use RoF link to extend radio- frequency (RF) signal connection and distribution to simplify the network architecture and reduce the cost [12–14]. Optical fiber is an excellent medium for RF signal transmission due to its high bandwidth (BW), low loss, light weight, small cross section and low cost. In this RoF link, a head-end (HE), which consists of an optical-to-electrical (O/E) and an electrical-to-optical (E/O) modules, is used to connect to the BS. A remote antenna unit (RAU) will be used in each picocell. Therefore, the WiMAX RoF system can employ a head-end (HE) and several RAUs to extend the cell coverage and reduce the cost and handover, as illustrated in Fig. 1(b).
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Automated Method For Fiber Length Measurement

Automated Method For Fiber Length Measurement

The camera also needed the capability to be hardware triggered to ensure that the fiber sensor would be able to control the camera. Hardware triggering refers to the ability to either provide a high signal or ground to a wire connected directly to the camera to cause it to capture an image. Software triggering and continuously capturing images are other common configurations for controlling cameras however they are not required for this system. The original system used a camera configured to continuously capture images and proved to be very effective. The fibers were moving much slower and at any given time there were many fibers within the frame. The new system however has a few quickly moving fibers and if the camera were to capture continuously, images would rarely contain fibers. The software trigger could potentially work, however it would require an analog input into the computer which would then need to determine if it is a signal high and then trigger the camera via software. This would require a significant amount of software integration along with a data acquisition system. While possible it was not practical and while software and continuous triggering may be beneficial for testing purposes hardware triggering is necessary to successfully integrate the camera into the system.
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The Measurement and Analysis of Bluetooth Signal RF

The Measurement and Analysis of Bluetooth Signal RF

Abstract. Aiming at the traditional Bluetooth signal test method exists the problem which can’t capture the characteristics of the signal frequency with time, a system to test the RF power of Bluetooth signal based on the frequency hopping characteristic of Bluetooth signal is proposed. Test system based on Bluetooth signals in single and multiple common abrupt pulse power measurement, a comprehensive study of the transmission power and test method, this paper analyzes the ACPR, ACLR, CCDF several parameters, such as performance indexes and its impacts on the Bluetooth signal power. The results in the paper will provide theoretical basis for the systematization and automation of Bluetooth RF power control, which has a great significance to maintain the quality of communication links, reduces the overall interference of the system and improves the overall performance.
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The Design of Fiber Bragg Grating Temperature Measurement System Based on Labview

The Design of Fiber Bragg Grating Temperature Measurement System Based on Labview

The design process of the system is shown in Figure 3. The basic parameters of software running are configured by starting the interface. If the initialization succeeds, the interface will shut down automatically and open the main interface at the same time. Then we choose the light channel and the 1 × 4 light switch, set the sensor model, integration time, noise threshold and load the data of calibration wavelengths corresponding to the pixels. Data collection is completed in the hardware system itself, which will send the instruction of getting spectra data to module by calling the library function node. When re- ceiving the response signal, the module began to obtain spectral data. Due to the limit of line array pixel of the PIN, the module will output 512 16-bit electrical signal data after the photoelectric conversion completed. Because of it, the spectrum data we receive is only 512 groups each time. The main program calls the target functions from link library WIN32Shared.DLL, reads the power value, channel wavelength values and optical signal-to- noise ratio from each pixel and gets the number of peaks and the corresponding wavelengths by the Gaussian func- tion.
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Radio over Fiber System Level Performance Analysis, Maintaining Signal Integrity

Radio over Fiber System Level Performance Analysis, Maintaining Signal Integrity

With Radio over Fiber is just sending the radio signals over optical fiber. Easy maintenance, low power units, simple remote antennas, low attenuation loss, large bandwidth and reduced power consumption are few benefits of RoF link. RoF is an auspicious solution to accomplish the increasing demand of wireless and user bandwidth. In RoF system the only task of Base station is to convert optical signal into Radio signal. Figure 1(a) shows layout of simple bidirectional directly modulated RoF link. Modulation, multiplexing, coding are performed at Central Unit CU. The receiver consists of Photodiode to provide an RF power output proportional to the square of the input optical power. In recent How to cite this paper: Kashif, R., Famo-
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An Automated Perifusion System for Modifying Cell Culture Conditions over Time

An Automated Perifusion System for Modifying Cell Culture Conditions over Time

useful for hormones released in this fashion such as in- sulin, luteinizing, and growth hormones [2, 3, 16]. The long-term goal of our work is to manipulate different cellular processes in the glucose-stimulated insulin secretion pathway to determine which of the multiple oscillatory systems in beta-cells may be important to long-term viability and function [17]. Long term studies can also be conducted to show the typical slow effect of hormonal changes such as in female ovulatory cycles [18]. In studies relating to pituitary hormones, many dif- ferent chemicals can be added automatically for long pe- riods to utilize these long lasting tissues to their full extent. Perifused pituitary tissues are known to release much more hormone when compared to static cultures [3]. In an example relating to pancreatic islets, the cells can be studied overnight without supervision to see the long term effect of perifusing different solutions. The calcium influx response or total insulin release of the β cells can then be analyzed. The pulsatile patterns we cre- ated in islets are similar to endogenous insulin pulses re- leased into the portal system that directly target the liver. Thus, the same simulated pulsatility could be valu- able to the study of hepatocytes [19, 20]. The automa- tion of the typical peristaltic perifusion system opens up many new possibilities for live culture studies.
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Automated Pattern Classification for PCG Signal as a Novel Method for Clinical Decision Support System

Automated Pattern Classification for PCG Signal as a Novel Method for Clinical Decision Support System

pattern associated with this technique raised from incomplete training sets or random noise spectra associated with acquired PCG signal, dynamic identification of diastolic and systolic murmurs can be corrected from associated noise by using FIR filtering implemented in the automated classification path to remove any parasitic acoustic noise which may occurred during data acquisition procedure [8,9].

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Study On An Automated Machine Signal Monitoring

Study On An Automated Machine Signal Monitoring

The use of intelligent systems expanding in the manufacturing industry to monitor the operation of computer numerical control (CNC). Many approaches had been proposed to achieve tool monitoring and certain of them had been well adapted to industrialized applications. The increasing popular approach is to analyse the acoustic emission (AE) obtained from machining cutting operation. Although its advantages, AE based systems is not considered to be truly reliable because (a) their sensitivity to AE is created via sources other than tool and workpieces which may be picked up by the sensor and confuse the signal processing task, (b) the need to adjust the signal amplification depending on the process to be monitored., (c) the sensitivity of AE measurement to sensor location and cutting parameters, and (d) constrained related to the practical implementation of a microphone in an industrial setting, such as directional consideration, frequency respond, and environment sensitivity (Denkena and Lepper, 2015). Figure 2.1 shows a CNC milling machine.
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