TECHNOLOGY AREA(S): Information Systems

ACQUISITION PROGRAM: Digital Modular Radio (DMR), Battle Force Tactical Network (BFTN), HForce

OBJECTIVE: Architect and develop a prototype High Dynamic Range Multi-Carrier Amplifier (HDR MCA) that can support up to 36 concurrent carriers with high individual carrier power variations and the resulting intermodulation interference in the Very High Frequency (VHF) and Ultra High Frequency (UHF) bands.

DESCRIPTION: The technology to be developed should:

a. Provide a VHF (30MHz - 300MHz) coupler system that incorporates technologies such as comb-filters and pre-distortion for up to 16 frequency channels that include single or multiple high-power amplifier(s) for each channel with frequency hopping, and at least 50dBW transmit power output without incurring significant interference effects (>3 dB).� The output of the amplifiers should provide sample transmitted signals so the transmissions can be cancelled from the separate receive antenna.� Optionally, the prototype HDR MCA may directly incorporate the interference cancellation feature; however, the samples of the transmitted signal must be provided as discreet outputs.� The VHF coupler system supports 16 hopping transmit channels with 5 dBm input per channel.� The number of channels supported should scale to 36 channels.

b. Provide an UHF (300MHz - 3GHz) coupler system and UHF amplifier with support for up to 24 frequency channels.

c. Provide linear amplification with Simultaneous Transmit and Receive (STaR) interference mitigation for Multi-Frequency Time Division Multiple Access (MFTDMA) carriers over the full High Frequency (HF) band (3MHz - 30MHz) with at least 50dBW total transmit power output and support MFTDMA channels with 5dBm input power.

PHASE I: Design an architecture for a HDR MCA that directly interfaces or integrates into the Digital Modular Radio (DMR) to yield high dynamic range amplification in VHF and UHF bands.� Additionally, the HDR MCA shall facilitate hosting of emerging advanced waveforms such as HF Over-the-horizon Communication (HFORCE) in the HF band on DMRs and emerging HF radio systems (e.g., PRC-117G).� Establish whether the amplifier can be produced as a single entity or a combination of multiple discreet amplifiers.� If multiple discreet amplifiers are to be utilized, provide a management and control architecture concept required to easily integrate the HDR MCA into the target system.� Develop the supporting amplifier architecture concept that will address high individual carrier power variations and mitigate the resulting intermodulation interference.

Identify the near term HDR MCA Pre-Planned Product Improvement (P3I) required for HFORCE's HF MFTDMA implementation in the 2025 timeframe.

Develop prototype plans for Phase II.

PHASE II: If multiple discreet amplifiers are to be utilized, then provide a management and control architecture required to easily integrate the HDR MCA in to the target system (initially DMR).� Develop the supporting amplifier architecture that will address high individual carrier power variations and mitigate the resulting intermodulation interference. Develop a set of performance specifications for HDR MCA for interfaces and/or direct integration into DMR.� Develop the prototype HDR MCA based on Phase I work for demonstration and validation in DMR.� Identify the preliminary lifecycle support strategies and concepts for HDR MCA to include Lowest Replaceable Unit (LRU), depot/contractor facility repair and/or maintenance, and sparing.

Establish a working relationship with a candidate HFORCE waveform contractor (Program Office will assist in the identification and introduction) to perform initial development of any necessary Pre-Planned Product Improvement (P3I) requirements to integrate HFORCE into DMR.

PHASE III DUAL USE APPLICATIONS: Refine, fully develop, and integrate the Phase II prototype HDR MCA into DMR.�� Integrate HDR MCA into a prototype HFORCE system for initial performance assessments.

Perform Formal Qualification Tests (FQT) of HDR MCA Production Representative Article (PRA) in the DMR against the performance specification for HDR MCA.

Support the fielding and maintenance of HDR MCA by implementing the lifecycle support strategies and concepts with the DMR and HFORCE waveform contractors.

The current trends in commercial 5G communications technology selection indicates the potential application of multi-carrier waveforms with highly varying peak to average power.� HDR MCA technologies may provide a solution for future 5G baseband towers with limited application on user terminals.

REFERENCES:

1. General Dynamics Mission Systems. Digital Modular Radio (DMR): Software-Defined Communications for the U.S. Navy, 2017, https://gdmissionsystems.com/radios/digital-modular-radio/

2. RF Power Amplifier. https://en.wikipedia.org/wiki/RF_power_amplifier

3. Bawa, Sangeeta. Pal, Maninder, and Gupta, Jyoti. �Pre-distortion Based Linearisation Technique for power Amplifiers of Wideband Communications Systems.� International journal of Scientific & Engineering Research, Volume 4, issue 5, May 2013, ISSN: 2229-5518. pp 726-733. https://www.ijser.org/researchpaper/Pre-distortion-Based-Linearisation-Technique-for-Power-Amplifiers-of-Wideband-Communication-Systems.pdf

4. Comb Filter. https://en.wikipedia.org/wiki/Comb_filter

KEYWORDS: HF; VHF; UHF; Multi-Carrier Amplifier; High Dynamic Range; Wideband; DMR; BFTN; HFORCE