Spitzer, C.R., Martinec, D.A., Leondes, C.T., Rana, A H, Check, W. " Aerosp The Electrical Engineering Handbook Ed. Richard C. dorf Boca Raton CRC Press llc. 2000
Spitzer, C.R., Martinec, D.A., Leondes, C.T., Rana, A.H., Check, W. “Aerospace Systems” The Electrical Engineering Handbook Ed. Richard C. Dorf Boca Raton: CRC Press LLC, 2000
102 Aerospace Systems Cary R. Spitzer Daniel a. martinec 102. 1 Avionics Systems Cornelius T Leondes University of California, San Diego Software in Avionics.CNS/ATM. Navigation Equipment Emphasis on Communications.Impact of "Free Flight Abdul Hamid Rana Avionics in the Cabin. Avionics Standards 102.2 Communications Satellite Systems: Applications Satellite Launch. Spacecraft and Systems. Earth Stations. VSAT William Check Communication System· Video· Audio· Second-Generation GE Spacenet 102.1 Avionics Systems Cary R. Spitzer, Daniel A. Martinec, and Cornelius T. Leondes Avionics(aviation electronics) systems perform many functions: (1)for both military and civil aircraft, avionics are used for flight controls, guidance, navigation, communications, and surveillance; and(2)for military aircraft, avionics also may be used for electronic warfare, reconnaissance, fire control, and weapons guidance and control. These functions are achieved by the application of the principles presented in other chapters of nis handbook, e.g., signal processing, electromagnetic, communications, etc. The reader is directed to these chapters for additional information on these topics. This section focuses on the system concepts and issues unique to avionics that provide the traditional functions listed in(1)above. Development of an avionics system follows the traditional systems engineering flow from definition and analysis of the requirements and constraints at increasing level of detail, through detailed design, construction validation, installation, and maintenance. Like some of the other aerospace electronic systems, avionics operate in real time and perform mission-and life-critical functions. These two aspects combine to make avionics system design and verification especially challenging though avionics systems perform many functions, there are three elements common to most systems: data buses, displays, and power. Data buses are the signal interfaces that lead to the high degree of integration found today in many modern avionics systems. Displays are the primary form of crew interface with the aircraft and in an indirect sense, through the display of synoptic information also aid in the integration of systems. Power, of course is the life blood of all electronics The generic processes in a typical avionics system are signal detection and preprocessing, signal fusion, computation, control/display information generation and transmission, and feedback of the response to the control/display information.(Of course, not every system will perform all of these functions. A Modern Example System The B-777 Airplane Information Management System(AIMS)is the first civil transport aircraft application of the integrated, modular avionics concept, similar to that being used in the U.S. Air Force F-22. Figure 102.1 shows the AIMS cabinet with eight modules installed and three spaces for additional modules to be added the AIMS functions are expanded. Figure 102.2 shows the AIMS architecture c 2000 by CRC Press LLC
© 2000 by CRC Press LLC 102 Aerospace Systems 102.1 Avionics Systems A Modern Example System • Data Buses • Displays • Power • Software in Avionics • CNS/ATM • Navigation Equipment • Emphasis on Communications • Impact of “Free Flight” • Avionics in the Cabin • Avionics Standards 102.2 Communications Satellite Systems: Applications Satellite Launch • Spacecraft and Systems • Earth Stations • VSAT Communication System • Video • Audio • Second-Generation Systems 102.1 Avionics Systems Cary R. Spitzer, Daniel A. Martinec, and Cornelius T. Leondes Avionics (aviation electronics) systems perform many functions: (1) for both military and civil aircraft, avionics are used for flight controls, guidance, navigation, communications, and surveillance; and (2) for military aircraft, avionics also may be used for electronic warfare, reconnaissance, fire control, and weapons guidance and control. These functions are achieved by the application of the principles presented in other chapters of this handbook, e.g., signal processing, electromagnetic, communications, etc. The reader is directed to these chapters for additional information on these topics. This section focuses on the system concepts and issues unique to avionics that provide the traditional functions listed in (1) above. Development of an avionics system follows the traditional systems engineering flow from definition and analysis of the requirements and constraints at increasing level of detail, through detailed design, construction, validation, installation, and maintenance. Like some of the other aerospace electronic systems, avionics operate in real time and perform mission- and life-critical functions. These two aspects combine to make avionics system design and verification especially challenging. Although avionics systems perform many functions, there are three elements common to most systems: data buses, displays, and power. Data buses are the signal interfaces that lead to the high degree of integration found today in many modern avionics systems. Displays are the primary form of crew interface with the aircraft and, in an indirect sense, through the display of synoptic information also aid in the integration of systems. Power, of course, is the life blood of all electronics. The generic processes in a typical avionics system are signal detection and preprocessing, signal fusion, computation, control/display information generation and transmission, and feedback of the response to the control/display information. (Of course, not every system will perform all of these functions.) A Modern Example System The B-777 Airplane Information Management System (AIMS) is the first civil transport aircraft application of the integrated, modular avionics concept, similar to that being used in the U.S. Air Force F-22. Figure 102.1 shows the AIMS cabinet with eight modules installed and three spaces for additional modules to be added as the AIMS functions are expanded. Figure 102.2 shows the AIMS architecture. Cary R. Spitzer AvioniCon Inc. Daniel A. Martinec Aeronautical Radio, Inc. Cornelius T. Leondes University of California, San Diego Abdul Hamid Rana GE LogistiCom William Check GE Spacenet
Generator FIGURE 102.1 Cabinet assembly outline and installation(typical installation).(Courtesy of Honeywell, Inc. AIMS functions performed in both cabinets include flight management, electronic flight instrument systen (EFIS)and engine indicating and crew alerting system(EICAS)displays management, central maintenance, irplane condition monitoring, communications management, data conversion and gateway(ARINC 429 and ARINC 629), and engine data interface AIMS does not control the engines nor flight controls, nor operate any internal or external voice or data link communications hardware but does select the data link path as part of the communications management function. Subsequent generations of AIMS may include some of these latter In each cabinet the line replaceable modules(LRMs)are interconnected by dual arinc 659 backplane data buses. The cabinets are connected to the quadraplex(not shown)or triplex redundant ARINC 629 fly-by-wire data buses and are also connected via the system buses to the three multifunction control units(MCDU)used by flight crew and maintenance personnel to interact with AIMS. The cabinets merged and processed data over quadruple redundant custom designed 100 Mhz buses to the EFIS and EICAS In the AIMS the high degree of function integration requires levels of system availability and integrity not found in traditional distributed, federated architectures. These extraordinary levels of availability and integrity are achieved by the extensive use of fault-tolerant hardware and software maintenance diagnostics and promise to reduce the chronic problem of unconfirmed removals and low mean time between unscheduled removals (MTBUR). Figure 102.3 is a top-level view of the U.S. Air Force F-22 Advanced Tactical Fighter avionics. Like many other aircraft, the F-22 architecture is hybrid, part federated and part integrated. The left side of the figure is the highly integrated portion, dominated by the two Common Integrated Processors(CIPs)that process, fuse, and distribute signals received from the various sensors on the far left. The keys to this portion of the architecture are the Processor Interconnect(PI)buses within the CIPs and the High Speed Data Buses(HSDBs).(There are provisions for a third CIP as the F-22 avionics grow in capability. The right side of the figure shows the federated systems including the Inertial Reference, Stores Management, Integrated Flight and Propulsion Con trol, and Vehicle Management systems and the interface of the latter two to the Integrated Vehicle System Control. The keys to this portion of the architecture are the triple or quadruple redundant AS 15531( formerly MIL-STD-1553)command/response two-way data buses. e 2000 by CRC Press LLC
© 2000 by CRC Press LLC AIMS functions performed in both cabinets include flight management, electronic flight instrument system (EFIS) and engine indicating and crew alerting system (EICAS) displays management, central maintenance, airplane condition monitoring, communications management, data conversion and gateway (ARINC 429 and ARINC 629), and engine data interface. AIMS does not control the engines nor flight controls, nor operate any internal or external voice or data link communications hardware but does select the data link path as part of the communications management function. Subsequent generations of AIMS may include some of these latter functions. In each cabinet the line replaceable modules (LRMs) are interconnected by dual ARINC 659 backplane data buses. The cabinets are connected to the quadraplex (not shown) or triplex redundant ARINC 629 system and fly-by-wire data buses and are also connected via the system buses to the three multifunction control display units (MCDU) used by flight crew and maintenance personnel to interact with AIMS. The cabinets transmit merged and processed data over quadruple redundant custom designed 100 Mhz buses to the EFIS and EICAS displays. In the AIMS the high degree of function integration requires levels of system availability and integrity not found in traditional distributed, federated architectures. These extraordinary levels of availability and integrity are achieved by the extensive use of fault-tolerant hardware and software maintenance diagnostics and promise to reduce the chronic problem of unconfirmed removals and low mean time between unscheduled removals (MTBUR). Figure 102.3 is a top-level view of the U.S. Air Force F-22 Advanced Tactical Fighter avionics. Like many other aircraft, the F-22 architecture is hybrid, part federated and part integrated. The left side of the figure is the highly integrated portion, dominated by the two Common Integrated Processors (CIPs) that process, fuse, and distribute signals received from the various sensors on the far left. The keys to this portion of the architecture are the Processor Interconnect (PI) buses within the CIPs and the High Speed Data Buses (HSDBs). (There are provisions for a third CIP as the F-22 avionics grow in capability.) The right side of the figure shows the federated systems including the Inertial Reference, Stores Management, Integrated Flight and Propulsion Control, and Vehicle Management systems and the interface of the latter two to the Integrated Vehicle System Control. The keys to this portion of the architecture are the triple or quadruple redundant AS 15531 (formerly MIL-STD-1553) command/response two-way data buses. FIGURE 102.1 Cabinet assembly outline and installation (typical installation). (Courtesy of Honeywell, Inc.)
CORTROL CONTROL 1I □□ R FIGURE 102.2 Architecture for AIMSbaseline configuration. Courtesy of Honeywell, Inc. Data buses As noted earlier, data buses are the key to the emerging integrated avionics architectures. Table 102. 1 summarizes the major features of the most used system buses. MIL-STD-1553 and ARINC 429 were the first data buses to be used for general aircraft data communications. These are used today widely in military and civil avionics, respectively, and have demonstrated the significant potential of data buses. The others listed in the table build on their success Displays All modern avionics systems use electronic displays, CRTs or flat-panel LCDs that offer exceptional flexibility in display format and significantly higher ity than electromechanical displays. Because of the ery bright ambient sunlight at flight altitudes the principal challenge for an electronic display is adequate brightness CRTs achieve the required brightness through the use of a shadow mask design coupled with narrow bandpass optical filters. Flat-panel LCDs also use narrow bandpass optical filters and a bright backlight to achieve the necessary brightness. e 2000 by CRC Press LLC
© 2000 by CRC Press LLC Data Buses As noted earlier, data buses are the key to the emerging integrated avionics architectures. Table 102.1 summarizes the major features of the most commonly used system buses. MIL-STD-1553 and ARINC 429 were the first data buses to be used for general aircraft data communications. These are used today widely in military and civil avionics, respectively, and have demonstrated the significant potential of data buses. The others listed in the table build on their success. Displays All modern avionics systems use electronic displays, either CRTs or flat-panel LCDs that offer exceptional flexibility in display format and significantly higher reliability than electromechanical displays. Because of the very bright ambient sunlight at flight altitudes the principal challenge for an electronic display is adequate brightness. CRTs achieve the required brightness through the use of a shadow mask design coupled with narrow bandpass optical filters. Flat-panel LCDs also use narrow bandpass optical filters and a bright backlight to achieve the necessary brightness. FIGURE 102.2 Architecture for AIMSbaseline configuration. (Courtesy of Honeywell, Inc.)
○ AIRDATA tutors Equipment Warno - Frequency FIGURE 102.3 F-22 EMD Architecture TABLE 102.1 Characteristics of Common Avionics Buses MIL-STD-1553 DOD-STD-1773 ARINC 629 002202 Fiber 50 Mb/s wire or fiber optic 2 Mb/s Wire or fiber optic ARINC 659 100 MB/s Because of the intrinsic flexibility of electronic displays, a major issue is the design of display formats. Care must be taken not to place too much information in the display and to ensure that the information is comprehendible in high workload(aircraft emergency or combat)situations Power Aircraft power is generally of two types: 28 vdc, and 115 vac, 400 Hz. Some 270 vdc is also used on military aircraft. Aircraft power is of poor quality when compared to power for most other electronics. Under normal conditions, there can be transients of up to 100% of the supply voltage and power interruptions of up to 1 second This poor quality places severe design requirements on the avionics power supply, especially where the avionics are performing a full-time, flight-critical function. Back-up power sources include ram air turbines and batteries, although batteries require very rigorous maintenance practices to guarantee long-term reliable per Software in avionics Most avionics currently being delivered are microprocessor controlled and are software intensive. The"power achieved from software programs hosted on a sophisticated processor results in very complex avionics with many functions and a wide variety of options. The combination of sophistication and flexibility has resulted e 2000 by CRC Press LLC
© 2000 by CRC Press LLC Because of the intrinsic flexibility of electronic displays, a major issue is the design of display formats. Care must be taken not to place too much information in the display and to ensure that the information is comprehendible in high workload (aircraft emergency or combat) situations. Power Aircraft power is generally of two types: 28 vdc, and 115 vac, 400 Hz. Some 270 vdc is also used on military aircraft. Aircraft power is of poor quality when compared to power for most other electronics. Under normal conditions, there can be transients of up to 100% of the supply voltage and power interruptions of up to 1 second. This poor quality places severe design requirements on the avionics power supply, especially where the avionics are performing a full-time, flight-critical function. Back-up power sources include ram air turbines and batteries, although batteries require very rigorous maintenance practices to guarantee long-term reliable performance. Software in Avionics Most avionics currently being delivered are microprocessor controlled and are software intensive. The “power” achieved from software programs hosted on a sophisticated processor results in very complex avionics with many functions and a wide variety of options. The combination of sophistication and flexibility has resulted FIGURE 102.3 F-22 EMD Architecture. TABLE 102.1 Characteristics of Common Avionics Buses Bus Name Word Length Bit Rate Transmission Media MIL-STD-1553 20 bits 1 Mb/s Wire DOD-STD-1773 20 bits TBS Fiber optic High-speed data bus 32 bits 50 Mb/s Wire or fiber optic ARINC 429 32 bits 14.5/100 kb/s Wire ARINC 629 20 bits 2 Mb/s Wire or fiber optic ARINC 659 32 bits 100 MB/s Wire