# A Model-Based Engineering Approach for Evaluating Software-Defined Radio Architecture
## 2 Descriptive Models
\begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline
**Req. No.** & **Req. Name** & **Req. Text** \\ \hline SR.1 & Process the Received Analog Signals & The SDR-MM shall accept analog signals with the characteristics specified in the ‘Input Analog Signal Characteristics’ and transform them into digital data. & The SDR-MM shall have multiple bandwidth digital data outputs without overheating the system. \\ SR.2 & Quality of Output Data: Number of Equivalent Narrow Band Outputs & The SDR-MM shall accept operational commands (on and off) from the External Host Computer/Processor and send out the status information. \\ SR.3 & Computer/Processor: Commands and Status & The SDR-MM shall accept an analog signal with the following characteristics: signal power in range of \(-87.7\) to \(-83.27\) dBm, frequency in range of 3–17 GHz, and signal bandwidth in range of 140–160 kHz. \\ SR.4 & Input Analog Signal Characteristics & The SDR-MM shall have external ports to accept DC power (28 VDC, 3.3 VDC, 5 VDC, 12 VDC 15 VDC) from the Power Supply. \\ SR.5 & Power Ports & The SDR-MM shall have external ports to accept ‘10 MHz Frequency Reference’ from TFNG to discipline all LOs used in the conversion process. \\ SR.6 & 10 MHz Frequency Reference Port & The SDR-MM shall have external ports to accept ‘1 PPS Analog Signal’ from TFNG to start the time (stroke) set into the FPGA timing registers. \\ SR.7 & 1 PPS Analog Signal Port & The SDR-MM shall have external ports to accept ‘System Sampling Clock’ from TFNG used to sampling strobe for ADC and reference for decimation in DDC. \\ SR.8 & System Sampling Clock Port & The SDR-MM shall have external ports to accept ‘GPS Epoch Time Message Port’ from the External Host Computer/Processor set timing registers in the FPGA to the time from the GPS Msg. \\ SR.10 & Processed Digital Data Ports & The SDR-MM shall have external ports to send the processed data (digital data) to the External Host Computer/Processor for detection processing. \\ SR.11 & Dissipate the Heat Generated by Signal Processing Function & The SDR-MM shall dissipate the heat generated during the signal processing to the Communication Enclosure Air Environment (CEAE) to maintain the Average Electronic Surface Temperature (AEST) at or below 130 \({}^{\circ}\)C. \\ SR.12 & SDR-MM Dimensions & The SDR-MM dimensions shall not exceed 20.32 cm \(\times\) 12.7 cm \(\times\) 7.62 cm (\(8^{\prime\prime}\times 5^{\prime\prime}\times 3^{\prime\prime}\)). \\ SR.13 & SDR-MM Max Mass & The total mass of the SDR-MM shall not exceed 3 kg (estimated based on similar SDR-MM). \\ SR.14 & SDR-MM Max Energy Consumption & The SDR-MM shall consume less than 100 watts (peak). \\ SR.15 & SDR-MM Elements & The SDR-MM shall have an enclosure subsystem that can withstand an impact force of 100 KN (estimated based on the total weight of the SDR-MM and safety factor of 2). \\ SR.16 & Support Weight of Subsystems & The SDR-MM shall have an Enclosure subsystem that can support the total weight of all other MM elements. \\ SR.17 & Support Weight and Provide Structural Support & The SDR-MM shall mechanically be mounted to the Communication System Structure to support its weight and provide structural support. \\ SR.18 & Corrosion and Leak Protection & The SDR-MM shall protect itself and internal components from corrosion and leaks. \\ SR.19 & SDR-MM Max Cost & The total cost of the SDR-MM shall be less than USD 15,000. \\ SR.20 & Accessing the Internal Components & The SDR-MM shall allow easy access to all system components located inside the Enclosure that allows for component replacement and maintainability \\ \hline \end{tabular}
\end{table} 
Table 1: System requirement derived from stakeholder needs. refines the stakeholder needs and requirements and shows how the main functions of each system interact with all the others. With this black box approach, we do not consider how analog signals are converted to digital data.