APAR Terminology
| TERM / ACRONYM | GENERAL DESCRIPTION | DESCRIPTION AS IT PERTAINS TO THE APAR DEVELOPMENT |
|---|---|---|
| Active Electronically Scanned Array (AESA) | A group of multiple Sub-array panels and DREX's that form the full radar apeture. | For APAR, each AESA will consist of 37 Sub-array panels (notionally). Ther are four such AESAs in the APAR design mounted in approximate orthogonal locations on teh NSF/NCAR C-130 aircraft. |
| Airborne Phased array Radar (APAR) | A novel PAR design of NCAR/EOL to be flown aboard the NSF/NCAR C-130 aircraft | The APAR system will consist of four radar front ends and a radra back ends attached to the NSF/NCAR C-130 aircraft. |
| Array Controller | Sub-system to control AESA components | Interfaces with the radar back end ot control the array elements to perform scan and calibration functions. |
| CDR | Critical Design Review | An immediate design review that occurs after the detail design is complete and prior to the fabrication of prototypes or pre-production models. This review is conducted to evaluate the design against the detailed requirements. It has many of the components of a PDR including the provision of assumptions and calculations used in the design, project progress, and risk management. A production assessment is often included. The CDR is the key output of the Sub-array panel spiral allowing One AESA APAR Spiral to begin. |
| Digital Receiver/Exciter (DREX) | Digital components that converts Analog-to-Digital and Digital-to-Analog RF radar signals | DREX interfaces to multiple TRMs as defined by the radar front end vendor. |
| Element | Radiating antenna element | Radio Frequency (RF) radiating element |
| FAT | Factory Acceptance Test | A process that evaluates the equipment during and after the assembly process by verifying that it is built and operating in accordance with design. |
| FDR | Final Design Review | Conducted after prototypes or preproduction units have been through verification testing. Problems encountered during this testing and the respective solutions are examined. Any necessary changes to the product with respect to performance, cost, reliability and manufacturing issues are agreed upon prior to the initiation of full-scale production. |
| FTA | Flight Test Acceptance | Develops and data during flight of an aircraft and then analyzes the data to evaluate the aerodynamic flight characteristics of the vehicle in order to validate the design, including safety aspects. The flight test phase accomplishes two major tasks: i) finding and fixing any design problems and ii) certification of the instrument for flight. |
| GTA | Ground Test Acceptance | Develop and gather data on the ground (and on the aircraft prior to flight) to test the instrument, software/hardware, and aircraft integration to validate that the instrument is installed correctly with the purpose to find and fix integration issues between the radar front end, radar back end and NSF/NCAR C-130 integration including cooling, power and other NSF/NCAR C-130 environmental requirements. |
| I&T RBE | Integrate/Test radar back end | Integration and test activities are scheduled events that test the interaction and operation of two or more integrated APAR development components. In this case, it is the radar back end with the radar front end. |
| ICD/ICDs | Interface Control Document(s) | Document(s) provide the electrical, mechanical, structural and software description of the interfaces between systems (e.g., radar front end and radar back end) and sub-systems (e.g., radar scheduler and array controller). |
| Line Replaceable Unit (LRU) | Self-contained radar component that can be replaced by NCAR/EOL personnel in the field or the laboratory environment | An LRU can be power supply, TRM, Sub-arry panel, DREX, etc. |
| LRU Demonstrator | NCAR/EOL working prototype of a Sub-arry panel | |
| PDR | Preliminary Design Review | Design concepts are evaluated for feasibility, technical adequacy, and general compliance with requirements, and the relative merits/weaknesses of different concepts are presented. Assumptions and calculations that led to conclusions are provided, and whenever possible, preliminary prototypes, mock-ups, or sketches are used to communicate the various concepts. The technical progress of the project is reviewed, as is the current and projected status of the budget and schedule. Potential risk items are highlighted and mitigation plans are evaluated. |
| Phased Array Radar (PAR) | A radar system consisting of multiple atenaa elements | By varying the phase of each element in a precise and prescribed way, the combined wave fronts form an interference pattern resulting in a plane wave that travels at a pre-determined angle with respect to the plane of the antennas. In this way, the beam can be scanned over a wide range of azimuth and elevation angles without the need for mechanical positioning of each individual antenna. |
| Radar Back End | Consists of all sub-systems mounted in the interior of the NSF/NCAR C-130. These sub-systems include signal processing, communications with the AESA, displays, data collection, etc. | For APAR, these sub-systems will be developed by NCAR/EOL with potential university partners. |
| Radar Front End | Consists of all sub-systems lying outside of the NSF/NCAR C-130 including: the AESAs and array controllers integrated with a power supply, liquid cooling system, mounting structure, and a radome. | For APAR, these sub-systems will be developed and built by an industry subcontractor. |
| SIT | System Integration Test | System Integration Testing is defined as a type of software testing carried out in an integrated hardware and software environment to verify the behavior of the complete system. It is testing conducted on a complete, integrated system to evaluate the system's compliance with its specified requirement. The final SIT is the acceptance criteria to transition APAR to the Operations stage. |
| Sub-array Panel (SAP) | Defined (by vendor) as the grouping of NxM Elements/TRMs that can operate together as a sub-unit of the AESA. By combining multiple Sub-array panels, antenna apertures of various sizes and shapes can be realized. | Each APAR Sub-array Panel is made up of 8x8 (notionally) antenna elements and TRMs. |
| SVT | Software Verification Test | Software verification is the process of evaluating the radar back end to ensure it is built per the specified requirements and demonstrates the consistency, completeness, and correctness of the software during each stage of the software development lifecycle. The radar back end testing cycle includes multiple SVTs. |
| Transmit/Receive Module (TRM) | Consists of Phase Shifters, Attenuators, Switches, Couplers, associated timing and control electronics. | The individual chain of C-Band radar RF components that trasmit (Tx) and receive (Rx) RF signals through the antenna element. |
| TRD | Technical Requirements Document | Defines technical/engineering level requirements that APAR must meet or exceed to meet and defines the requirements to fulfill the radar front end contract. |
| TRR | Test Readiness Review | Conducted to determine if the system under review is ready to proceed into formal testing by deciding whether the test procedures are complete and verify their compliance with test plans and descriptions. A TRR is normally conducted before each major test configuration item including hardware and software and provides management with the assurance that a system has undergone a thorough test process and is ready for turnover to the next test phase. The Flight Readiness Review (FRR) is a subset test of the TRR. |