Spectrum Dominance: Delivering LPI/LPD and Anti-Jamming Capabilities Without Sacrificing Performance

Tactical Communication Challenges in the Era of Great Power Competition

As the modern electromagnetic battlespace rapidly evolves, the stakes for robust and resilient tactical communications networks across mission-critical defense applications has never been higher. As near-peer adversaries continue to develop and deploy advanced electronic warfare (EW) capabilities, traditional radio systems have struggled to adapt to these new and unique operational challenges.

The Rising Need for Secure & EW Resilient Tactical Communications

In the future fight, the warfighter’s ability to operate in congested and contested radio frequency (RF) spectrum environments and persist in the presence of adversarial interference and jamming has emerged as a critical need. In addition, the U.S. Department of Defense Joint All-Domain Command & Control (JADC2) strategy envisions empowering Joint Force Commanders with the capabilities needed to connect sensors to shooters across all warfighting domains, and throughout the electromagnetic spectrum, regardless of where the future battlespace may be.

Silvus Technologies’ Spectrum Dominance was purpose-built to meet these challenges, delivering next-generation Low Probability of Intercept/Low Probability of Detection (LPI/LPD) and Anti-Jamming (AJ) capabilities to the warfighter, enabling them to achieve decision dominance and communications superiority on the battlefield.

Silvus’ MIMO-enabled MANET technology value proposition is simple: higher throughput, longer ranges, scalability, and reliable, repeatable performance. With Spectrum Dominance, we’re guaranteeing that same level of performance in a contested EW environment.

Spectrum Dominance is an expansive suite of LPI/LPD and AJ capabilities that provide secure and EW-resilient mesh network communications at the tactical edge. Silvus’ Spectrum Dominance enables StreamCaster MANET radios (AN/PRC-169) and MN-MIMO waveform to thrive in congested and contested environments, empowering operators to achieve mission objectives even in the presence of multi-tiered electronic attacks.

Layered Approach to LPI/LPD & Anti-Jam Defense 

Spectrum Dominance takes a layered approach to LPI/LPD concealment and AJ defense, forcing an adversary to penetrate all layers to disrupt communications. The first layers are dedicated to LPI and LPD covertness – concealing or reducing the radio’s signal signature. If an adversary can’t detect it, they can’t take action against you. 

An LPD feature, MANET Power Control (MAN-PC) minimizes the RF footprint of StreamCaster MANET radios – dynamically throttling power to the minimum amount necessary to maintain network connectivity. In addition, when features such as MANET Protected Waveform (MAN-PW) are enabled, the MN-MIMO waveform is hardened for increased resiliency against electronic attacks.

With Spectrum Dominance, every radio in the Silvus MN-MIMO mesh network performs real-time spectrum analysis and interference monitoring. Upon the detection of interference, Spectrum Dominance employs Anti-Jam resiliency techniques to mitigate electronic attack.


As an example, MANET Interference Cancellation (MAN-IC) utilizes multiple antennas to employ sophisticated spatial signal processing techniques to nullify the offending interfering signal, without suppressing one’s own signal.  Additionally, MANET Interference Avoidance (MAN-IA), automatically scans and monitors the RF spectrum for interference across multiple user-defined channels. At the onset of jamming, the entire network moves to the cleanest frequency without user intervention.

Silvus is the only MANET provider that delivers Spectrum Dominance capabilities without sacrificing range, throughput, or robustness

Program Notables & Use Cases

The real-world use cases of Spectrum Dominance are well documented. Silvus StreamCaster MANET radios, MN-MIMO waveform, and Spectrum Dominance capabilities have been adopted across multiple U.S. Department of Defense branches, establishing Silvus as the leading tactical communications provider in support of key modernization programs. 

Recently, Silvus StreamCaster MANET radios were selected for expanded deployment in the Army’s Integrated Tactical Network (ITN), for their ability to provide secure and protected high bandwidth networking and situational awareness data connectivity. In addition, with Spectrum Dominance’s advanced interference avoidance and cancellation capabilities, Silvus StreamCaster MANET radios and MN-MIMO waveform are able to thrive in congested and contested spectrum environments.

A critical component of achieving the Army’s Unified Network modernization objectives, the ITN is designed to provide a common operating environment (COE) for joint force mission coordination at the tactical edge and is a critical enabler of JADC2.

Silvus StreamCaster MANET radios with Spectrum Dominance capabilities were also recently selected for the  U.S. Marine Corps Networking On-the-Move Mobile Communications System for the Joint Light Tactical Vehicle (JLTV) and Amphibious Combat Vehicle (ACV). As the first MANET radio added to the NOTM mobile communications system, Silvus StreamCaster 4400 MANET radios enable the Marine Air-Ground Task Force to access satellite communications, connect and network dispersed vehicles, airborne assets, and dismounted units through a protected and EW resilient communications architecture.

The complete suite of Spectrum Dominance capabilities is available to U.S. Government customers via firmware updates through downloadable licenses. Several of Silvus’ non-ITAR controlled Spectrum Dominance features are commercially available to all Silvus customers.

Spectrum Dominance – Achieve Spectrum Overmatch In Any Operational Environment 

Silvus Technologies is dedicated to one mission: Solving the toughest communication problems facing the warfighter.

As the world’s leading developer of advanced MANET radio systems, powered by Silvus’ revolutionary MN-MIMO waveform, Silvus Technologies is reshaping mesh network technology for mission-critical applications – on the ground, in the air and at sea.

Serving Defense, Law Enforcement, Public Safety and Commercial customers around the world, the Silvus StreamCaster family of MANET radios provide high-fidelity video, voice and IP data communications – providing actionable intelligence at the speed of relevancy.

At Silvus, we never stop innovating comms technology for the tactical edge.

Revolutionary MN-MIMO Waveform Technology

At the heart of every StreamCaster MANET radio is Silvus’ proprietary MN-MIMO waveform technology – capable of linking hundreds of nodes with unmatched Range, Data Throughput, EW Resiliency and Scalability.

As a software licensable extension of the Silvus MN-MIMO waveform, Spectrum Dominance’s expansive suite of LPI/LPD and AJ resiliency capabilities provide secure and robust communications enabling operators to achieve RF Spectrum Overmatch in any Operational Environment.

Learn More

Download the Spectrum Dominance Capabilities Profile or contact us today to learn how Silvus is delivering communications superiority and decision dominance at the tactical edge.



Non-line-of-sight (NLOS) Propagation in Mobile Ad-hoc Networks

An Introduction to NLOS Propagation

In wireless communications, understanding non-line-of-sight (NLOS) propagation is essential to creating and deploying robust Mobile Ad-hoc Networks (MANET). Unlike line-of-sight (LOS) propagation which operates without impairments, NLOS propagation refers to the transmission of communication signals in scenarios where a direct and unobstructed path between the transmitter and receiver is not present. 

NLOS environments are characterized by impairments that range from unknown obstacles and terrain features to even distant environmental objects that can attenuate, distort or scatter the radio’s communication signal. In dense, urban environments, NLOS challenges are abundant – buildings, structures and moving vehicles can create obstacles, reflections, or multi-path environments that alter a signal’s trajectory and its integrity.  

NLOS propagation plays an essential role in modern wireless and MANET radio communications. In MANET networks every radio acts as a transmitter, receiver, and communications relay.  This enables each radio link and the entire mesh network to automatically route data along the optimal path to reach its destination.  By using radios as relays, MANET networks adapt to their environment, enabling signals to traverse NLOS obstacles, expanding their network coverage area or distance and enabling connectivity in complex environments.  

For communication network operators and RF engineers, understanding the dynamics and capabilities of NLOS propagation is essential to architecting wireless networks that can overcome environmental challenges, and provide the vital communication link for mission-critical applications. 

This edition of the Waveform Blog provides insights into the challenges of NLOS, and the techniques and solutions available to enhance MANET radio communications. 

Factors Affecting NLOS Propagation

With NLOS propagation, various factors come into play, each influencing the reliability and performance of wireless communications. To gain a better understanding, we first need to dissect contributing NLOS factors and their ramifications in MANET radio mesh networks

Fresnel Zone

An elliptical region between the transmitter and receiver, the Fresnel Zone plays a pivotal role in NLOS propagation. Obstacles within this zone, such as buildings or terrain features can obstruct the signal’s path, causing signal loss. In densely populated urban environments, where structures permeate the landscape, the Fresnel Zone’s integrity is often compromised, posing significant challenges to communication reliability.  As a rule of thumb, Fresnel Zone obstructions are typically quantified as a 6dB loss in signal – that equates to achieving half the distance of signal range in free space. 

Environmental Obstructions

Buildings, vegetation, trees and even moving vehicles can disrupt signal propagation and create signal reflectors that bounce radio waves off their surfaces. This can lead to multi-path effects that scatter and attenuate the signal, making it challenging to maintain consistent communications. 

Earth and Atmosphere 

The earth’s curvature and atmospheric conditions can introduce signal refraction and bending, affecting the trajectory of radio waves. This bending can lead to unexpected signal paths that impact NLOS propagation much like direct line-of-sight (LOS) obstructions. In long-range communications across rugged terrain, the earth’s curvature becomes a critical factor to consider.    

Together, these factors collectively contribute to the degradation of signals in NLOS scenarios, affecting communication reliability, data rates and coverage area. Network and RF engineers designing and optimizing wireless networks must meticulously account for these variables to ensure robust communication connectivity.

NLOS Propagation Solutions

Coded Orthogonal Frequency-Division Multiplexing (COFDM)

COFDM is a digital multiplexing technique where the waveform is split into multiple subcarriers with data sent on each carrier. This enables multiple bits of data to be transmitted in parallel across multiple streams with information redundancy. In NLOS environments characterized by reflections, data becomes extremely frequency-selective – with different levels of signal attenuation and data loss. Some frequencies experience little to no loss, while others will experience heightened signal attenuation. As one of the key characteristics of Silvus MN-MIMO waveform, COFDM counteracts the effects of frequency selectivity on data loss, enabling the data to be recovered because it has been redundantly coded onto other subcarriers. 

Multiple-Input, Multiple-Output (MIMO) Antenna Techniques 

MIMO operates on a simple yet powerful principle – employing multiple antennas at both the transmitter and receiver to improve the range, throughput, and robustness of wireless communications. When a signal travels through a dynamic NLOS environment, MIMO equips it with resilience. It splits the signal into multiple streams transmitted each over distinct antennas – and at the receiving end reconstructs it to become a stronger, more robust version. 

MIMO-based waveform technology, such as Silvus’ proprietary MN-MIMO waveform leverages these advanced MIMO antenna techniques to counter the adverse effects of NLOS, enabling signals to outmaneuver tactical RF challenges.


Unlike traditional high-gain antennas or amplifiers, Eigen-Beamforming adapts dynamically, irrespective of antenna orientation or line-of-sight obstacles. By adjusting the phase and amplitude of the transmitted signal to leverage the optimal eigen modes of the channel, Eigen-Beamforming ensures that the optimal signal is always sent to the receiver, even in the presence of high multi-path environments in an NLOS channel. Additionally, because Eigen-Beamforming is done on each subcarrier independently, it can be used in conjunction with other techniques such as COFDM to increase throughput even across frequency-selective channels.  Therefore, because it’s not adversely affected by scattering objects or reflections, Eigen-Beamforming thrives in complex, and cluttered NLOS environments, with the ability to create up to 4x effective transmit power and range. 

Space-Time Coding 

As its name implies, Space-Time Coding takes the digitized signal from the radio and adds redundancy to it in both space and time.  Space refers to the physical distance between the antennas on a MIMO radio, allowing for added diversity and robustness. In addition, the bits of the digitized signal are also coded in time, with redundant bits sent into the channel at different time intervals to counteract any time-based variations in the NLOS environment. 

Spatial Multiplexing 

Utilizing multiple antennas operating at an identical center frequency, Spatial Multiplexing enables the transmission of multiple unique information streams from these different antennas. A communications network comprised of MIMO antennas at both the transmitter and receiver side, can then decode these streams individually and thus increase the amount of data flowing through a fixed channel bandwidth. Because it has the ability to increase the spectral efficiency (bits per second per Hz of the channel) of these data streams, Spatial Multiplexing is a core MIMO technique in delivering unsurpassed data rates in mobile, multi-path and NLOS environments. 

NLOS Propagation – Application Use Case Scenario

Consider a military or public safety team navigating a complex urban environment. Through the use of MANET radios and MIMO waveform technology, these teams can experience seamless communications between ground personnel, vehicles, and their command centers, even when buildings or other environmental conditions obstruct their line-of-sight. Adaptive MANET mesh networks, MIMO antenna techniques, COFDM and Eigen-Beamforming work together to enable NLOS propagation, enabling signals to adapt dynamically to their environment. Space-Time Coding enables data robustness and Spatial Multiplexing helps to maximize data rates – ensuring mission-critical information isn’t lost as it flows through the communications network. 

The result: strong NLOS propagation with clear and robust high-fidelity video, voice, and IP data connectivity without the need for a dedicated infrastructure.

Silvus Technologies – Empowering Connectivity In NLOS Environments

As the world’s leading developer of advanced MANET radio systems, powered by Silvus’ proprietary MN-MIMO waveform, Silvus Technologies is reshaping mesh network technology for mission-critical applications – on the ground, in the air and at sea. 

Our StreamCaster MANET radios and MN-MIMO waveform are purpose-built to outmaneuver Tactical RF challenges in NLOS environments with class-leading throughput, range, EW resiliency and scalability. On a mission to solve the toughest communication problems on the planet, Silvus continues to push the limits of tactical communications delivering next-generation capabilities to Defense, Public Safety and Commercial customers around the world.  

At Silvus, we never stop innovating comms technology for the tactical edge.

Want to Learn More?

Check out the case study on TX Eigen-Beamforming or Contact Us today to learn how Silvus can help you solve your most difficult communication challenges.



MIMO Communication Systems Technology

Radios & Antennas Working Together To Maximize Tactical Networking Capabilities

Reliable, robust and scalable wireless communications are vital for users who need to stay connected and coordinate actionable intelligence in challenging spectrum environments.  Multiple-input, Multiple-output or MIMO radio systems are a key enabler of creating powerful Mobile Ad-hoc Networks (MANET), that provide secure and reliable connectivity across a variety of operational applications. When used in conjunction with MIMO antennas they can be a force multiplier for creating powerful and adaptive mesh networks that unify operational assets in any environment. 

This edition of the Waveform Blog provides insights into MIMO-based radio systems and antennas, and how they can be used to create a high-performance tactical communications architecture for today’s mission-critical applications.

The Role and Importance of MIMO Communication Systems

At its core, MIMO communication systems utilize multiple antennas at both the transmitter and receiver ends to send and receive different data streams of a signal simultaneously. By processing signals from multiple paths, MIMO radio systems can mitigate the impact of noise and interference, resulting in vastly improved communication performance over legacy single antenna transceiver systems (SISO)

In addition, with their ability to create multiple parallel data streams that deliver high bandwidth throughput, MIMO communication systems provide users with scalable network connectivity solutions that operate reliably in dynamic and complex RF environments. 

With a variety of MIMO radio form factors and MIMO antenna design choices readily available, system operators have integration flexibility options across multiple use cases, with the ability to create custom-tailored solutions to meet their network and mission requirements.  

Today, MIMO communication systems deliver increased performance and reliability, making them an essential technology for mission-critical defense, law enforcement, public safety and commercial broadcasting applications. 

MIMO Communication Systems Advantages

MIMO communication systems provide significant benefits across multiple use-case applications, making them a preferred choice for organizations deploying reliable communications networks. Some of their critical advantages include: 

Increased reliability

Exploiting multiple signal paths makes MIMO-based communication systems more robust, particularly in areas where obstacles, or surfaces that bounce and reflect signals are present. Through the use of spatial diversity, MIMO communications systems can even use the environment to its advantage – leveraging reflections and scattering to enable signals to take multiple paths between the transmitter and receiver. This diversity helps reduce signal fading and improve communication reliability in challenging and dynamically changing environments. The key takeaway is that with MIMO communications systems, users are not required to create unobstructed sightlines for communications – allowing them the freedom and ability to execute missions in complex environments or across multiple domains (land, sea, air).  

Enhanced redundancy

With MIMO communication systems, multiple antennas transmit and receive data packets simultaneously. In addition, through the use of Space-Time Coding, the bits of the digitized signal are also coded in time, with redundant bits sent at different intervals to counter-act any time-based variations in the environment. The end result is robustness through redundancy – if you have a packet loss on one data stream, the other streams will compensate, resulting in fewer losses of vital data communications. 

Elevated throughput

Through the use of Spatial Multiplexing and Eigen-Beamforming, MIMO communication systems enable users to transmit large amounts of data at high throughput rates. Spatial Multiplexing utilizes multiple antennas to transmit multiple unique information streams. A communications network that features MIMO-based radios and antennas at the transmitter and receiver ends can then decode these streams individually, increasing the amount of data flowing through. Eigen-Beamforming works slightly differently – adjusting the phase and amplitude of the transmitted signal to ensure that the optimal signal is always sent to the receiver. When used together, these two techniques are particularly valuable for high bandwidth operations including real-time video streaming, remote surveillance and other data-intensive applications. 

Enhanced visual and auditory quality

A MIMO communications system uses multiple antennas at the transmitter and receiver side to create spatial degrees of freedom. Because of its ability to combine and reconstruct multiple data streams simultaneously, a MIMO communications system can eliminate noise or image corruption – providing users with the highest possible visual and auditory quality. 

Expanded flexibility

Because MIMO communication systems for tactical Mobile Ad-hoc Networks are not constrained by fixed infrastructure limitations, they can rapidly be adapted based on changing channel and operational conditions. Communication network operators and RF engineers have multiple choices in the types of MIMO radios and antennas used, enabling them to custom tailor networked solutions based on their operational tempo. By utilizing adaptive signal routing and other advanced MIMO antenna techniques, these systems enable RF signals to navigate complex and multi-path, non-line-of-sight environments, creating a robust and flexible communications network across multi-domain operations (air, land, sea).   

MIMO Radio & Antenna Options – An Overview 

Silvus StreamCaster Radio

Typically characterized by its number of antenna ports, MIMO radios come in a variety of form factors ranging from 2×2 MIMO handheld battery-powered radios that can be easily integrated into tactical vests, to externally powered 4×4 MIMO radios that can be temporarily or permanently mounted to vehicles or fixed infrastructure. In addition, each of these radio types typically offers OEM or radio module versions, allowing the physical layer of the radio to be installed and directly connected to manned or unmanned vehicle sub-systems.  Because of their bi-directional ability – to both send and receive different data streams simultaneously – MIMO radios excel at delivering high-fidelity video, voice and IP data communications. This translates into a superior radio experience for its operators, providing high bandwidth connectivity coupled with operational flexibility.  

MIMO radios are compatible with both Single Input, Single Output (SISO) and MIMO antennas. SISO antennas feature a single port, and rely on the MIMO radio to send, receive and process signals through it. MIMO antennas, on the other hand, contain multiple ports with integrated functional elements that are used to transmit and receive signals simultaneously, thereby optimizing data throughput and enhancing radio connectivity performance. Often in MIMO antennas, their functional elements are polarized opposite of each other for improved signal performance in complex operational environments, with both single and dual frequency band configurations. 

Omni Antennas

A SISO antenna type, Omnidirectional antennas radiate equal power in all directions, making them a flexible choice for tactical MANET radio applications. Typically attached directly to the radio or connected via RF cables, Omni antennas provide 360° RF antenna patterns across single or dual frequency bands. Operators can also choose from a range of low to high gain, and horizontal to vertical polarity to customize the performance and RF signature of their communications network. 

Panel Antennas

Available in both SISO and MIMO configurations, Panel antennas directionally radiate power, providing improved performance and coverage over focused areas of operation. This high degree of energy and beam focus enables them to overcome environmental obstacles. Panel antennas provide use case flexibility through quick-deploy mast options or fixed installations. 

Patch Antennas

A low-profile variant of the panel antenna available in both SISO and MIMO configurations, patch antennas provide a directional RF antenna pattern but with higher gain with a more focused beamwidth than Omnidirectional antennas. With a compact size, patch antennas range from body-worn to mobile/vehicular and installed configurations.  

High-Gain Sector Antennas

These MIMO antennas concentrate their signals in a specific area or sector, providing an efficient use of available power and data throughput over extended ranges. To achieve multi-sector coverage, multiple high-gain sector antennas can be combined to create 360° of coverage. 

Dish Antennas

These parabolic-shaped MIMO antennas provide high gain and high throughput over long distances. Because they produce the narrowest beamwidth of any antenna type within a focused area of operation, Dish antennas used in wireless communications networks are typically tracking antenna variants, that include automatic azimuth calibration and 360° rotation to maximize their operational effectiveness.   


MIMO Communication Systems Applications

MIMO Communication Systems applications are as varied as their form factor options. Their robust network capacity and increased area coverage combined with operational flexibility provide effective connectivity options for tactical to long-range applications. 

Defense, law enforcement and public safety

MIMO communication systems are vital in defense, law enforcement and public safety applications, providing secure and reliable network connectivity in complex and austere operational environments. With the ability to unify operational assets including personnel, vehicles, command centers and manned/unmanned aircraft, agencies typically employ a variety of MIMO-based radio and antenna types to create scalable mesh networks that deliver mission success.  

Aerospace and aviation

MIMO communications systems enable high-bandwidth data and communications downlink and relays between the aircraft, control center and ground-based personnel. When used together with MIMO technology this results in minimized signal latency and optimized spectral efficiency, ensuring high throughput communication links that are crucial for operational efficiency and safety in congested airspaces.

Unmanned Systems

With their bi-directional ability to both send and receive data streams simultaneously, MIMO communication systems are instrumental in enhancing C2, data downlinks and communication relay capabilities for unmanned systems ranging from stratospheric and high-altitude platform systems (HAPS) and unmanned aerial vehicles (UAV), to unmanned ground vehicles (UGV) and unmanned surface vessels (USV). Given the critical nature of many unmanned missions, secure and EW-resilient communications are essential for mission success. MIMO communication systems provide this operational capability, ensuring robust connectivity and improved situational awareness at greater stand-off range and in contested environments.  

Broadcasting and multimedia

MIMO communications systems stand out for their unique spatial multiplexing capabilities, allowing broadcasters to transmit multiple data streams over the same frequency band. This, combined with advanced MIMO radio and antenna techniques paves the way for high-definition signal reception even in congested spectrum environments and complex urban environments with multi-path reflections.

Acting as a force multiplier for operational teams, MIMO communication systems create a powerful MANET mesh network that connects and unifies communications throughout your area of operation – from personnel, vehicles and command posts to long-range unmanned and manned aircraft. 

Silvus MIMO Radios

As the world’s leading developer of advanced MIMO communication systems, powered by Silvus’ proprietary MN-MIMO waveform, Silvus Technologies is reshaping mesh network technology for mission-critical applications – on the ground, in the air and at sea. Purpose-built to outmaneuver tactical RF challenges in any environment with class-leading throughput, range, EW resiliency and scalability, our family of StreamCaster MANET radios delivers next-generation capabilities to Defense, Public Safety and Commercial customers around the world. To learn more, visit the StreamCaster Radios page.

StreamCaster Radios

Silvus MIMO Antennas

Silvus’ StreamCaster PRISM family of Precision Integrated Sectorized MIMO antennas is a modular solution that combines the performance of StreamCaster MANET radios with high-gain, dual polarity sector antennas to deliver up to 360° of coverage for tactical to fixed infrastructure applications. To learn more, visit the StreamCaster PRISM page.

StreamCaster PRISM

Silvus StreamCaster TRINITY Dual Band MIMO Transceiver Array delivers high bandwidth, long-range mesh network communications in any environment. Featuring a unique Trilobe design, each of StreamCaster TRINITY’s three, high-gain 12 dbi sector antennas provides 120° of coverage, extending the area of operation for manned/unmanned air and ground assets. Use them independently or together to achieve up to 360° of coverage

StreamCaster Trinity


Your Mission Is Our Mission: 

Silvus Technologies is dedicated to one mission: Solving the toughest communication problems on the planet. 

Since Silvus’ founding, we’ve pioneered MIMO communication technology, culminating in the release of the world’s first ever tactical MIMO radio. Through groundbreaking research & development, Silvus’ team of top PhD scientists and design engineers continue to innovate MIMO communications for the tactical edge, enabling new capabilities and applications for customers in high-stakes industries. 

Through everything we do, we take a partnership approach – bring us your most difficult communication problems and we’ll help you solve them with MIMO communication technologies that just work. 


Learn More

Contact Us Today to learn how Silvus is delivering advanced MIMO Communication Systems Technology
for mission critical applications in any operational environment.