SpeakEasy was a

United States military The United States Armed Forces are the military forces of the United States. The armed forces consists of six service branches: the Army, Marine Corps, Navy, Air Force, Space Force, and Coast Guard. The president of the United States is th ...

project to use software-defined radio technology to make it possible to communicate with over 10 different types of

military radio Military communications or military signals involve all aspects of communications, or conveyance of information, by armed forces. Military communications span from pre-history to the present. The earliest military communications were delivered ...

s from a single system.

History

"The SpectrumWare project applied a software-oriented wireless communications approach with distributed signal processing. The research direction of the SpectrumWare project was heavily influenced by two software radio efforts: the military SpeakEasy project and the commercial products of the Steinbrecher Corporation. According to Upmal and Lackey in “SPEAKeasy, the Military Software Radio”

IEEE Communications Magazine The ''IEEE Communications Magazine'' is a monthly magazine published by the IEEE Communications Society dealing with all areas of communications including light-wave telecommunications, high-speed data communications, personal communications syst ...

(NY: IEEE Press) 1995, the SpeakEasy project was started in 1991 and was the first large-scale software radio. SpeakEasy was motivated in large part by the communications interoperability problems that resulted from different branches of the military services having dissimilar (non-interoperable) radio systems. This lack of communications interoperability can be directly linked to casualties in several conflicts. SpeakEasy had a very aggressive goal of implementing ten different radio waveforms in software on a single platform. The designers chose the fastest

DSP DSP may refer to: Computing * Digital signal processing, the mathematical manipulation of an information signal * Digital signal processor, a microprocessor designed for digital signal processing * Yamaha DSP-1, a proprietary digital signal ...

available at the time, the Texas Instruments TMS320C40 processor, which ran at 40 MHz. Since this was not enough processing power to implement all of the waveform processing, the system boards were designed to each support four ’C40s as well as some

FPGAs A field-programmable gate array (FPGA) is an integrated circuit designed to be configured by a customer or a designer after manufacturinghence the term '' field-programmable''. The FPGA configuration is generally specified using a hardware de ...

. In 1994, Phase I was successfully demonstrated; however it involved several hundred processors and filled the back of a truck.

Moore’s Law Moore's law is the observation that the number of transistors in a dense integrated circuit (IC) doubles about every two years. Moore's law is an observation and projection of a historical trend. Rather than a law of physics, it is an empiri ...

provides a doubling in speed every eighteen months, and since it had taken three years to build the system and write all of the software, two doublings had taken place. This seemed to indicate that the number of processors could be reduced by a factor of four. However, SpeakEasy could not take advantage of these newer faster processors, and the reason was the software. The software was tied to ’C40 assembly language, plus all of the specialized

glue code Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advant ...

to get four C40s to work together with the code for the particular chosen FPGA. The observation was that it had taken three years to write software for a platform that Moore’s Law made obsolete in eighteen months. Further-more, a software radio pushes most of the complexity of the radio into software, so the software development could easily become the largest, most expensive part of the system. These observations led to

software portability A computer program is said to be portable if there is very low effort required to make it run on different platforms. The pre-requirement for portability is the generalized abstraction between the application logic and system interfaces. When ...

being a key goal of the SpectrumWare project."

References

{{DEFAULTSORT:Speakeasy Military radio systems of the United States Software-defined radio

History

See also

References