Design of Local Oscillator Based on DDS of High Performance Short-Wave Receiver

2013 ◽  
Vol 834-836 ◽  
pp. 1140-1144 ◽  
Author(s):  
Yong Tai Chen ◽  
Chang Jing Sun ◽  
Bin Zang ◽  
Long Cheng ◽  
Jing Tang ◽  
...  
Keyword(s):  
High Performance ◽  
Gain Control ◽  
Local Oscillator ◽  
Short Wave ◽  
Frequency Multiplier ◽  
Test Results ◽  
Frequency Range ◽  
Front End ◽  
Tracking Filter ◽  
Spurious Signals

Phase noise and spurious signals of local oscillator will affect the performance of short-wave receiver. The structure of receiver's front-end part based on DDS is introduced to realize a high-performance local oscillator of short-wave receiver. Then measures were taken to improve the LO's performance, including using external directly frequency multiplier as DDS' clock to improve the purity of frequency spectrum, tracking filter to degrade harmonics and gain control circuit to remain constant amplitude in the desired frequency range. At last, test results show that the above-mentioned measures improve the receiver's performance.

scholarly journals Downconverting Module Architectures for High Performance Multipixel Cameras

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Diego Palombini ◽  
Maciej Jankowski ◽  
Ernesto Limiti
Keyword(s):  
High Performance ◽  
Local Oscillator ◽  
Frequency Range ◽  
Frequency Multiplication ◽  
Band Frequency ◽  
System Architectures ◽  
Sky Surveys ◽  
And Performance ◽  
Scanning Systems ◽  
Speed And Accuracy

Multipixel cameras represent an emerging topology for arrays receivers, improving speed and accuracy of both security scanning systems and radioastronomical sky surveys by means of a matrix of phased elements. Difficulties in the generation and proper distribution to each pixel of the local oscillator signal still limit their use to frequency ranges below a few GHz or at least seriously affect the complexity of the implementable cameras. This work presents a full comparison between two possible system architectures, alternatively based on LO frequency multiplication or subharmonic mixing strategies, aiming to overcome the aforesaid limitations: design and performance of two compact test vehicles in MMIC technology, both operating in the Q-band frequency range with ultrabroadband IF section, are reported.

Design and Implementation of a Digitally Tunable Tracking Preselected Filter for Ultra Short Wave Receiver

2013 ◽  
Vol 712-715 ◽  
pp. 1755-1759
Author(s):  
Yong Tai Chen ◽  
Li Juan Su ◽  
Chang Jing Sun ◽  
Sen Ye ◽  
Jing Tang
Keyword(s):  
Short Wave ◽  
Test Results ◽  
Resonant Structure ◽  
Design And Implementation ◽  
Front End ◽  
Design Requirements

Design of a digitally tunable tracking preselected filter for improving anti-interference for Ultra Short Wave receiver front-end is proposed in this paper and the characteristics of the preselected filter circuit are analyzed. Then we mainly discuss an inductor-coupled dual resonant structure with better selectivity and anti-jamming and its implementation. Finally, test results are provided, shown the specifications of the circuit are in great agreement with the simulation and design requirements.

Design of the Millimeter-Wave Receiver

2014 ◽  
Vol 662 ◽  
pp. 235-238
Author(s):  
Shuang Zhao ◽  
Dian Ren Chen
Keyword(s):  
Millimeter Wave ◽  
Communication Systems ◽  
Second Harmonic ◽  
Local Oscillator ◽  
Frequency Component ◽  
High Frequency Component ◽  
Bottom Surface ◽  
Test Results ◽  
Electronic Warfare ◽  
Front End

The millimeter-wave transceiver front-end as a subsystem of high-frequency component is an important part of the radar, navigation, electronic warfare and communication systems. The millimeter receiver front-end developed herein, using the second harmonic mixer, reduces the frequency of the local oscillator. Using the bottom surface outlet ladder microstrip - waveguide structure, it strengthens the structure. Test results show that the developed front-end receiver has gain of 25dB and the transmit band is 35.5-36GHz.

Requiem for the STAT Test: Automation and Point of Care Testing

2019 ◽  
Author(s):  
Gurmukh Singh ◽  
Natasha M Savage ◽  
Brandy Gunsolus ◽  
Kellie A Foss
Keyword(s):  
Point Of Care ◽  
Turnaround Time ◽  
Test Automation ◽  
Test Results ◽  
Point Of Care Testing ◽  
Tube System ◽  
Front End ◽  
Laboratory Test Results ◽  
Batch Testing ◽  
Pneumatic Tube System

Abstract Objective Quick turnaround of laboratory test results is needed for medical and administrative reasons. Historically, laboratory tests have been requested as routine or STAT. With a few exceptions, a total turnaround time of 90 minutes has been the usually acceptable turnaround time for STAT tests. Methods We implemented front-end automation and autoverification and eliminated batch testing for routine tests. We instituted on-site intraoperative testing for selected analytes and employed point of care (POC) testing judiciously. The pneumatic tube system for specimen transport was expanded. Results The in-laboratory turnaround time was reduced to 45 minutes for more than 90% of tests that could reasonably be ordered STAT. With rare exceptions, the laboratory no longer differentiates between routine and STAT testing. Having a single queue for all tests has improved the efficiency of the laboratory. Conclusion It has been recognized in manufacturing that batch processing and having multiple queues for products are inefficient. The same principles were applied to laboratory testing, which resulted in improvement in operational efficiency and elimination of STAT tests. We propose that the target for in-laboratory turnaround time for STAT tests, if not all tests, be 45 minutes or less for more than 90% of specimens.

Age and Performance Under Pressure

2012 ◽  
pp. 134-152 ◽  
Author(s):  
Harold O. Fried ◽  
Loren W. Tauer
Keyword(s):  
Correlation Coefficient ◽  
High Performance ◽  
Age Distribution ◽  
Mental Ability ◽  
Trade Off ◽  
Athletic Ability ◽  
Front End ◽  
Ladies Professional Golf Association ◽  
And Performance ◽  
Performance Under Pressure

This article explores how well an individual manages his or her own talent to achieve high performance in an individual sport. Its setting is the Ladies Professional Golf Association (LPGA). The order-m approach is explained. Additionally, the data and the empirical findings are presented. The inputs measure fundamental golfing athletic ability. The output measures success on the LPGA tour. The correlation coefficient between earnings per event and the ability to perform under pressure is 0.48. The careers of golfers occur on the front end of the age distribution. There is a classic trade-off between the inevitable deterioration in the mental ability to handle the pressure and experience gained with time. The ability to perform under pressure peaks at age 37.

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