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Fragmented Spectrum Efficiency Manager


OBJECTIVE: Research and develop programmable RF transceiver technology, including software, hardware and documentation capable of fragmenting one RF transmission into multiple RF fragments and reassembling fragments post reception to original composite. DESCRIPTION: This Fragmented Spectrum Efficiency Manager (FSEM) system effort is intended to provide communications capability to deliver detection-resistant timely mission command & tactical intelligence and situational awareness in all environments. Use of Commercial Off The Shelf (COTS) products are important but not to the extent of restricting research. The solution must demonstrate coherent processing in the fragmenting of a transmission and distribution of fragments of spectrum to four or more geosynchronous satellite paths. The solution must also demonstrate the aggregation of the fragments post satellite transmission. Therefore this effort requires at least two independent hardware elements to operate geographically separated. The FSEM fragmenting and aggregating will function in the frequency range of 1 to 2 GHz (L-Band). The FSEM must however interface to a frequency conversion component for transport and address satellite communications latencies associated frequencies from C through Ka band. The FSEM must also interface with satellite modems in the same frequency range as the frequency conversion interface. The solution can utilize overhead framing techniques but efficiency must be great enough to stay below the 5% bandwidth overhead utilization threshold. Lastly, the energy per bit, commonly referenced to a 0 dB noise figure (written in the industry as Eb/N0) can grossly impact data throughput. Power levels from path to path will vary. Satellite link performances can range from unusable to completely error free within 2 dB Eb/N0. The energy per bit performance at the receive part of the modem will be a strong metric in terms of receive quality of a satellite link in assessing FSEM aggregation performance. The solution should incorporate leveling and phase techniques to enable optimized aggregation. The means to fragment a spectrum transmission into 4 or more segments and re-aggregating fragments successfully recovering the original data error free within the original composite post aggregation with low bandwidth cost is the technical risk associated with this effort. The FSEM fragmenting processor will have only one L-Band carrier SMA input and at least four L-Band SMA fragment outputs. As a threshold requirement, each input and output of the FSEM fragmenting processor must handle a single carrier bandwidth range of 38.4 KHz through 40 MHz with an objective requirement of 150 Hz (or lower) through 1 GHz (or higher). The FSEM fragmenting processor number of outputs must be programmable by the user to distribute fragments between 0-100 percent of the original composite input up to at least four spectrum outputs, including: replicating 100% to one channel; 100% to each channel; and non-replicated, uneven distribution. As an example, the FSEM fragmenting distribution non-replicated across four channels can be: 10%, 25%, 30% and 35%. Interfacing signal levels range from +5 to -40 dBm. The FSEM aggregating processor will be completely independent of the FSEM fragmenting processor and have a corresponding minimum of four L-Band SMA inputs and one L-Band SMA output. Each FSEM aggregating processor channel input/output carrier bandwidth requirements are the same as the FSEM fragmenting processor. Interfacing signal levels range from -25 to -70 dBm. PHASE I: In Phase I, the contractor shall develop the architecture and the design approach for the programmable Fragmented Spectrum Efficiency Manager (FSEM) system. The architecture and design should, at a minimum, meet the threshold requirements identified in the Description paragraph, above. Existing technologies such as inverse multiplexing and packetizing are referenced as known architectures and will not be acceptable as a Phase I deliverable due to the circuit dependencies requiring feedback, bit stuffing and packetizing which are inefficient methods in a SATCOM environment. The design must be state of the art and reflect agility in programmatically replicating in a non-symmetrical fashion fragments of bandwidth across four or more channels in a single direction and be re-aggregated at the receiving end using overhead costs within the threshold cited above. The design must show the encoding and preamble methods used on the transmission disassembly that provides a method of recovery at the receiver with means to handle the varied latencies and levels encountered in the reassembly process. PHASE II: In Phase II, the contractor shall build, test and deliver a prototype Fragmented Spectrum Efficiency Manager (FSEM) tool system in accordance with the design delivered in Phase I, to include all required hardware, software and user documentation. The prototype shall incorporate commercial and/or military standards on all interfaces. The contractor shall develop and deliver a test methodology that includes Government approved test plan, test procedures, verification cross reference matrix (VCRM) and script files as necessary for testing. The contractor shall support demonstration testing at the Joint Satellite Engineering Center (JSEC) laboratory at Aberdeen Providing Ground for one week. The prototype system shall, at a minimum, meet the threshold requirements identified in the Description paragraph, above. The prototype will be tested with multiple spectral transmissions for disassembly and reassembly. The prototype is required to be programmable and must be able to be pre-configured by an operator to disassemble/reassemble at programmable spectrum fragments and programmable bandwidth distribution sizes. The disassembly will be handled at one location and the reassembly will be handled at a different location therefore the prototype must consist of two physical elements each capable of being programmed and operated independently. PHASE III: In Phase III, the Fragmented Spectrum Efficiency Manager (FSEM) prototype design will be refined, optimized and productized for transition to military Programs of Record and commercial applications. All circuitry, fabrication and interfaces must utilize industry recommended or military standards (i.e.; MIL-STD-530, RS-422, etc.) wherever possible and must meet safety standards prior to delivery and be labeled in accordance with best Commercial practices. The Fragmented Spectrum Efficiency Manager (FSEM) system has the potential for use in multiple emerging transmission technologies, where there is a need for coherent fragment disassembly and reassembly along multiple transmission lines. Immediately, the system will provide an inherent passive Anti-Jam (AJ)/Anti-Scintillation (AS) capability which will undergo testing upon delivery. The current focus is on emerging and existing military communications systems, but this technology may also be of use in commercial areas requiring high volume data communications, including video. Military efforts such as Future Advanced SATCOM Terminals (FAST) are launching efforts to expand the digital domain in today"s transponded SATCOM. Creating a means to programmatically traverse multiple polarizations offers a robust means of communications impervious to man-made scintillation and interference that if appropriately productized can be utilized throughout DoD.
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