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Article
Publication date: 27 January 2022

Sirasani Srinivasa Rao and Subba Ramaiah V.

The purpose of this research is to design and develop a technique for polyphase code design for the radar system.

Abstract

Purpose

The purpose of this research is to design and develop a technique for polyphase code design for the radar system.

Design/methodology/approach

The proposed fractional harmony search algorithm (FHSA) performs the polyphase code design. The FHSA binds the properties of the harmony search algorithm and the fractional theory. An optimal fitness function based on the coherence and the autocorrelation is derived through the proposed FHSA. The performance metrics such as power, autocorrelation and cross-correlation measure the efficiency of the algorithm.

Findings

The performance metrics such as power, autocorrelation and cross-correlation is used to measure the efficiency of the algorithm. The simulation results show that the proposed optimal phase code design with FHSA outperforms the existing models with 1.420859, 4.09E−07, 3.69E−18 and 0.000581 W for the fitness, autocorrelation, cross-correlation and power, respectively.

Originality/value

The proposed FHSA for the design and development of the polyphase code design is developed for the RADAR is done to reduce the effect of the Doppler shift.

Details

International Journal of Pervasive Computing and Communications, vol. 19 no. 3
Type: Research Article
ISSN: 1742-7371

Keywords

Content available
Article
Publication date: 1 December 2001

95

Abstract

Details

Sensor Review, vol. 21 no. 4
Type: Research Article
ISSN: 0260-2288

Content available
Article
Publication date: 1 December 2001

199

Abstract

Details

Industrial Lubrication and Tribology, vol. 53 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 1 August 1958

The background of missile costs is discussed. Missiles are new and very costly. Developments in this field have been subjected to political vicissitudes which have often upset…

Abstract

The background of missile costs is discussed. Missiles are new and very costly. Developments in this field have been subjected to political vicissitudes which have often upset long‐term developments. Missile technology is on the frontier of science and there is no background of knowledge to draw on; much basic and expensive research is required. Missile engineering models are complex in detail and assembly, and therefore costly, and constant change occurs while making and testing the model. The complexity and functional requirements of missile parts are running a parallel race with the machines and processes being developed to fabricate the materials required. The usually small runs required in missile production again add to costs. Imposed on all these activities is the requirement that reliability of near 100 per cent is needed and in no case can reliability be allowed to be secondary to cost. The inflight life and shelf conditions for a missile are usually fairly well established and 100 per cent reliability for a short operating life with a long shelf life are the real requirements. There is a considerable tendency to overdesign for reliability. Some costly features of design such as finest finish, closest tolerances and highest strength are carried over by habit from aircraft design and are not always required in missiles. Having examined some causes of high costs, a programme for cost reduction is set out. Costs can be reduced by: (i) earlier freezing of designs making changes only in groups of several changes at wider intervals, (ii) making a more realistic approach to reliability designs, (iii) selecting tolerances in a more analytical manner according to individual needs, (iv) selecting materials on the basis of actual design requirements instead of using the very best materials available even when the short life makes them unnecessary, (v) avoiding tool‐room methods in production engineering, (vi) setting work standards on as many operations as possible and enforcing them to the greatest degree possible, (vii) selecting the best type of workers to make the transition from development models to production missiles as smooth as possible, and (viii) setting up rigid systems and parts designation procedures for handling production parts. Finally, methods of organizing research and development and production for bridging the gap between engineering design and production are proposed.

Details

Aircraft Engineering and Aerospace Technology, vol. 30 no. 8
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 August 1974

Aeronautical & General Instruments Ltd, will exhibit their R 128 recording cameras, designed to photograph the information displayed on the cathode ray tube of an aircraft's…

Abstract

Aeronautical & General Instruments Ltd, will exhibit their R 128 recording cameras, designed to photograph the information displayed on the cathode ray tube of an aircraft's reconnaissance radar.

Details

Aircraft Engineering and Aerospace Technology, vol. 46 no. 8
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 26 July 2021

Nicole Gomes Dias, Beltran Nadal Arribas, Paulo Gordo, Tiago Sousa, João Marinho, Rui Melicio, António Amorim and Patrick Michel

This paper aims to report the first iteration on the Light Detection and Ranging (LIDAR) Engineering Model altimeter named HELENA. HELENA is a Time of Flight (TOF) altimeter that…

Abstract

Purpose

This paper aims to report the first iteration on the Light Detection and Ranging (LIDAR) Engineering Model altimeter named HELENA. HELENA is a Time of Flight (TOF) altimeter that provides time-tagged distances and velocity measurements. The LIDAR can be used for support near asteroid navigation and provides scientific information. The HELENA design comprises two types of technologies: a microchip laser and low noise sensor. The synergies between these two technologies enable developing a compact instrument for range measurements of up to 14 km. Thermal-mechanical and radiometric simulations of the HELENA telescope are reported in this paper. The design is subjected to vibrational, static and thermal conditions, and it was possible to conclude by the results that the telescope is compliant with the random vibration levels, the static load and the operating temperatures.

Design/methodology/approach

The Asteroid Impact & Deflection Assessment (AIDA) is a collaboration between the NASA DART mission and ESA Hera mission. The aim scope is to study the asteroid deflection through a kinetic collision. DART spacecraft will collide with Didymos-B, while ground stations monitor the orbit change. HERA spacecraft will study the post-impact scenario. The HERA spacecraft is composed by a main spacecraft and two small CubeSats. HERA will monitor the asteroid through cameras, radar, satellite-to-satellite doppler tracking, LIDAR, seismometry and gravimetry.

Findings

The HELENA design comprises two types of technologies: a microchip laser and low noise sensor. The synergies between these two technologies enable developing a compact instrument for range measurements of up to 14 km.

Originality/value

In this paper is reported the first iteration on the LIDAR Engineering Model altimeter named HELENA. HELENA is a TOF altimeter that provides time-tagged distances and velocity measurements. The LIDAR can be used for support near asteroid navigation and provides scientific information. The HELENA design comprises two types of technologies: a microchip laser and low noise sensor. The synergies between these two technologies enable developing a compact instrument for range measurements of up to 14 km.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 1 June 2003

Forrest Bishop

Several spacecraft beam‐propulsion concepts are introduced. “Mesoparticle beam propulsion” uses a collimated beam of mesoscopic particles, very roughly on the order of a nanogram…

Abstract

Several spacecraft beam‐propulsion concepts are introduced. “Mesoparticle beam propulsion” uses a collimated beam of mesoscopic particles, very roughly on the order of a nanogram mass each. Molecular nanotechnologies may permit the inclusion of entire guidance systems in each particle. “Micro Lightsails for beam propulsion” proposes matter‐beams composed of small, thin film lightsails with nanoscale components. Pushing a spacecraft with small, high velocity lightsails may be currently viable. “Ultracold matter beam generators” are proposed as a new type of space‐based particle‐beam. Design‐variants include a laser‐cooled thermal jet and a laser‐cooled, neutralized‐ion beam. Possible uses include the shipment of condensed, ultracold matter through space, the formation of an “artificial aerobraking corridor”, and beam‐propulsion for micro and nanospacecraft.

Details

Aircraft Engineering and Aerospace Technology, vol. 75 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 1 May 1975

APPLIED Technology, Middle East and European marketing and technical support representative of PF Industries Inc, will exhibit ground support equipment supplied to airlines…

Abstract

APPLIED Technology, Middle East and European marketing and technical support representative of PF Industries Inc, will exhibit ground support equipment supplied to airlines worldwide.

Details

Aircraft Engineering and Aerospace Technology, vol. 47 no. 5
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 September 1972

The Airlite 71 headset has a clip in facility on a boom arm for the rapid interchange of microphones. This includes the Dyn‐A‐Mike microphone plus pre‐amplifier for the…

Abstract

The Airlite 71 headset has a clip in facility on a boom arm for the rapid interchange of microphones. This includes the Dyn‐A‐Mike microphone plus pre‐amplifier for the replacement of carbon microphones.

Details

Aircraft Engineering and Aerospace Technology, vol. 44 no. 9
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 January 1964

IN covering British activities in the inertial guidance field, it is appropriate to include a brief picture of developments in the historical sense so that British achievements…

Abstract

IN covering British activities in the inertial guidance field, it is appropriate to include a brief picture of developments in the historical sense so that British achievements can be seen in perspective especially with regard to the state‐of‐the‐art in the United States. We will also deal with the application of inertial navigation systems to the civil field for, although at the moment every production inertial quality system in service is being operated in a military rôle, civil aviation is on the threshold of adopting inertial techniques.

Details

Aircraft Engineering and Aerospace Technology, vol. 36 no. 1
Type: Research Article
ISSN: 0002-2667

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