HLD - OTHR
Abstract
HLD-OTHR efforts focus on the development of a capability to extend current NWS surveillance to long range early warning for North America in response to emerging threats. The program will design, develop, test and field advanced 6th generation OTHR systems operating at levels of transmit power and receiver sensitivity far exceeding current OTHR systems in operation. Program activities include C2 interface design and integration, HF sensor and digital receiver technology advancement, ionospheric characterization research, remote sensor management capability development, and sensor data fusion research. HLD-OTHR data will be distributed and integrated into existing integrated air and missile defense (IAMD) early warning networks, to include the emerging DAF Battle Network and Cloud Based C2 architectures as applicable. Funds were added in FY24 to evaluate and develop improvements to the OTHR sensors tracking algorithms to increase probability of detection of high-altitude air vehicles such as stratospheric balloons and other unidentified aerial phenomena. Fielding involves land-based installation of Transmit and Receive site arrays for bi-static operations. Transmit sites require 140 acres of land and consist of vertical antennas in an array. Receive sites require 1350 acres of land and will consist of a 7-row, 2-dimensional antenna array. Additional development will include the establishment of an Operational Control Center (OCC) and associated Command and Control Battle Management capability to enable the dissemination of track data and other targets of interest for Air and Cruise Missile Defense of the Homeland (ACMD-H) air domain awareness requirements. Program Element will also be utilized to fund any emerging or urgent joint operational OTHR needs as required. This program element may include necessary civilian pay expenses required to manage, execute, and deliver weapon system capability. The use of such program funds would be in addition to the civilian pay expenses budgeted in program element 0605827F, 0605828F, 0605829F, 0605831F, 0605832F, 0605833F, 0605898F, 0606398F. In FY24 $4.2M was expended for civilian pay expenses in this program element, and in FY25 $4.3M is forecasted for civilian pay expenses in this program element. This program is in Budget Activity 7, Operational System Development because this budget activity includes development efforts to upgrade systems that have been fielded or have received approval for full rate production and anticipate production funding in the current or subsequent fiscal year.
Document Details
- Document Type
- Project
- Publication Date
- Oct 01, 2025
- Source ID
- 674592_0102417F_7_3600_PB_2025
Related Documents
- Root: Over-the-Horizon Backscatter Radar
- Child Accomplishment: Homeland Defense OTHR Development
- Child Cost Item: 6c6ea61dc2863094af7972fd6a415543
- Child Cost Item: aac8e55a79a122f74ba2c15a2d57c2db
- Child Cost Item: 8093ed18633d92dcb4c3d43634a77bc1
- Child Cost Item: 3fd1fc73cfc7286684b146e7fde5c08e
- Child Cost Item: b2c38c668ce9422f884935cc624be611
- Child Cost Item: 221721f0be341459930d0ae879a75b26
- Child Cost Item: a7cf7fb5793fc996602fcd0fca68c6ec
- Child Cost Item: c5528e3cdb8b01cbcb00329cb65fdfc2