The goal was to build 50 to 53 stations in total, with a total of 13,000 dipole antennas strategically placed in an area nearly 400 kilometres (250 miles) in diameter. However, the plan now is to deploy the system across the whole United States so as to expand its capability and increase the range of objects it can observe. The system can scan the sky at HF and VHF frequencies.
The first station, located adjacent to the NRAO's VLA, consists of 256antennas and was completed in December 2009. It was dedicated in April 2010, and routine operations began in 2011.
The second station (LWA2) was under construction about 19km (12mi) away as of 2011[update]. The array later came to be known as the LWA-SV.
In 2012, the LWA announced that they have successfully become a University Radio Observatory and is sponsored by the National Science Foundation. They also announced the first round of results from the LWA-1. In the same year, the OVRO-LWA array started to appear in literature, with the planning and construction starting the very next year in 2013.
From 2013 to 2014, the team, along with OVRO and CalTech, commenced work on the first stage of the OVRO-LWA array. The array consists of 251 elements.
LWA-SV (Sevilleta) consists of 256 antennas located in the Sevilleta National Wildlife Refuge. The LWA team installed the electronics shelter in April, 2014, and the array was subsequently completed on October 17th, 2015. The shelter is a 8x9.5x20 ft container with EMI shielding. In addition, work commenced on Stage II of the OVRO-LWA array, adding another 32 antennas and correlators, extending the baseline to 1.5km, with works completed in 2020.
In January, 2024, the OVRO-LWA array at the Owens Valley Radio Observatory of CalTech and sponsored by the National Science Foundation began routine operation. Initially planned for the 58 MHz to 85MHz range with 251 elements (Stage I), then to 283 elements (Stage II), with the array eventually came to become a 352 element array operating at 15 to 85MHz (Stage III).
The LWA-NA, located around 0.5km from the VLA, came online in 2023, supplementing the capabilities of the existing LWA network by allowing longer baselines, more astronomical observations, etc. The station is connected to the VLA through a 1GBps datalink and comes with more than 20% of recycled materials from previous trials and setups.
On June 13th, 2025, the LWA-MC (Meteor Crater) site at Arizona State University received its first antenna set for testing.
As of February, 2026, the LWA-1 and LWA-NA are being commissioned after major upgrades, while the LWA-SV array is totally offline as upgrades are underway.
The system was designed with two main goals: scientific discoveries and student S&T trainings. Hence, the system is designed to be modular for hands-on testing and verifications, while being able to innovate with the pace of technology. The system also comes in standardized parts and blueprints so as to enable future expansions.
We are one of the last remaining university radio observatories where students can actually go out and be part of every aspect of construction and operations of a radio telescope
—Greg Taylor, Distinguished Professor on Physics and Astronomy at University of New Mexico,
Students from the SunRISE Ground Radio Lab and Marquette Senior High School measuring the base of a Long Wavelength Array element during antenna assemblyStudents from the SunRISE Ground Radio Lab and Marquette Senior High School installing the electronics gear for a Long Wavelength Array element
System Design
The antennas come in four inverted V shape structures arranged in a X-like structure when seen from above, each functioning as a dipole. The design allows the system to distinguish between left-handed polarization and right-handed polarization. The antennas are with a declination of -30° to 90° and a bandwidth of 19.6 MHz. As the system utilizes dipole-based designs, the need for giant dishes is effectively eliminated, allowing students to work hands-on owing to its low size, weight, and price (SWaP) footprint. Each antenna stands about 1.5 metres (5ft) high and about 2.7 metres (9ft) across the base.
Three data products can be obtained from the LWA-1 array, namely TBW, TBN, and DRX, with one additional data product originally obtainable now inaccessible owing to unknown reasons. The inaccessible data product will probably not be back online anytime soon per the LWA team even after overhauls, as per their plan. For the LWA-SV array, there are four products obtainable, namely TBF, TBN, DRX, and COR.
The LWA-SV and LWA-1 systems operate within the range of 10MHz to 88 MHz, producing a cumulative 1TB per hour, with each full station spanning a diameter of around 100m with a minimum separation of 5m between the antennas. The OVRO-LWA site (Long Wavelength Array at Owens Valley Radio Observatory), on the other hand, operates within the range of 12MHz to 85 MHz, generating more than 50TB in 24 hours.
Network Design
The sites currently (as of October, 2026) within the network are:
LWA-1: full station, consists of 256 elements
LWA-SV: full station, consists of 256 elements
LWA-NA: flagship mini-station, consists of 64 elements
OVRO-LWA: special station, consists of 352 elements
Hillsdale College also currently operates a smaller 13-antennae array called the Low-Frequency All-Sky Monitor in addition to its contributions in the LWA-NA array, with routine tours to the LWA-1 and LWA-SV tours so as to gain familiarity with the system.The array exemplifies the S&T training mission assigned to the project since its inception.
The mini-station, or "LWA Swarm Stations", come in two formations, 48-element-type and 64-element-type, both with a minimum usable life of over 20 years. The stations are to Upgrading from 64-element-type to a full station of 256 elements is also possible. The flagship mini-station, the LWA-NA, came with a commercially available American Products Freedom series shelter, with the dimension being 78x90x42 inch, which is different from the customized 8x9.5x20 ft container for the previous full station efforts.
Each mini-station part cost approximately $112,000 to build and around $7,000/year in upkeep, and the full station's parts cost $600,000 each with a cumulative cost of around $1M each to build.
The sensitivity of the system is drastically higher than that of the LOFAR, which is already higher than the VLA, coming with a SEFD of around 1 MJy when using a single antenna and 6KJy and 24KJy for the full stations and the mini-stations respectively when measured per station.
Expanded Long Wavelength Array
The Expanded Long Wavelength Array (ELWA), or sometimes abbreviated as eLWA, is formed with LWA-SV and LWA-1 in conjunction with the 27 operating antennas from the Very Large Array. For the sake of convenience, ones who would like to access the ELWA system only need to apply through the VLA's portal without the need to make two proposals separately. Ones who are granted access to the ELWA through the VLA application system is automatically granted LWA usage.
The project was formally commissioned in 2018 and operates with a designed bandwidth of 10 MHz. The project was formed through a consortium between the Long Wavelength Array team, National Radio Astronomy Observatory, Virginia Tech, and Harvard-Smithsonian Center for Astrophysics to better utilize the low frequency capabilities of both systems, extending the baseline so as to improve observational capabilities.
The ELWA operates with a center frequency of 76MHz and a bandwidth of 8MHz during routine operations per the 2027A observing session. By using very-long-baseline interferometry (VLBI), the system has an effective aperture of nearly 100km.
DLITE
The Deployable Low-Band Ionosphere and Transient Experiment (DLITE) is a low-cost radio telescope based on the LWA technology for everybody use.
