This study defines a hardware architecture approach for software defined radios to enable commonality among NASA space missions. The architecture accommodates a range of reconfigurable processing technologies including general purpose processors, digital signal processors, field programmable date arrays (FPGAs), and application specific integrated circuits (ASICs) in addition to flexible and tunable radio frequency (RF) front ends to satisfy varying mission requirements. The hardware architecture consists of modules, radio functions, and interfaces. The modules are a logical division of common radio functions that comprise a typical communication radio. This paper describes the architecture details, module definitions, the typicalfunctions on each module and the module interfaces. Trade-offs between component-based, custom architecture and a functional-based, open architecture are described. The architecture does not specify a physical implementation internally on each module, nor does the architecture mandate the standards or ratings of the hardware used to construct the radios.