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# **Project Description:**
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The RFFEv1 is a four channel analog RF Front-End designed and optimized
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for 476 MHz operation (but easily optimizable for 450-520 MHz). Four
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calibration schemes were designed to improve the performance in terms of
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linearity (Beam Current Dependence) and long term stability.
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Resume of the calibration schemes:
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On-line pilot-tone: Couple a reference RF signal to the beam signal into
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the four RF chains at the same time.
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Off-line pilot-tone: Couple a reference signal to each of the RF
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channels, one by one, turning off the beam signal.
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Temperature controller: The RFFEv1 has 14 RTD's and distributed heaters
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on the board in order to implement control loop outside the PCB.
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Crossbar switching: Provides a crossbar scheme to swap the RF channels
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2x2.
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The RFE electronics is the analog processing part of the BPM electronics
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system designed by the LNLS Beam Diagnostics Group for the Sirius
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synchrotron accelerator.
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The RFFE electronics is composed by three boards. The RF analog
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electronics for channels A and C, the analog electronics for channels B
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and D and by the digital control board. This manual is related to the
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two RF analog conditioning boards, that are intended to provide gain,
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calibration and filtering to the RF beam signals that come from 25 meter
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of cables from the Beam position Monitor.
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Hardware Characteristics:
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\- Four RF channels providing Active Gain Control with attenuation
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ranging from 0 dB up to 30 dB.
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\- The central frequency can be changed by a footprint compatible SAW
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filter. From 400 MHz up to 550 MHz.
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\- High linear design, achieving less than +-0.001 dB nonlinearity over
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-35 dBm to -10 dBm
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\- On-chip Crossbar switching that improves drift and noise performance
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from ~DC up to half the switching frequency
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\- Input LPF before RF active devices are used in order to avoid peak
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voltages
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\- Physically separated channels to provide better electromagnetic
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isolation
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\- High Reliability connectors. Footprint compatible with other standard
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connectors
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\- Temperature control for the input LPF in order to keep its insertion
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loss constant
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## **Project Specification:**
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attachment:RFFE\_Specification\_Document\_v2.pdf
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<table>
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<tbody>
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<tr class="odd">
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<td><strong>Parameter</strong></td>
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<td><strong>Value</strong></td>
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<td><strong>Unit</strong></td>
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</tr>
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<tr class="even">
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<td>Dynamic Range</td>
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<td>40</td>
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<td>dB</td>
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</tr>
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<tr class="odd">
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<td>Input Power Range</td>
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<td>-50 to -10</td>
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<td>dBm</td>
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</tr>
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<tr class="even">
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<td>Delta-over-Sum</td>
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<td>1E-4</td>
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<td>-</td>
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</tr>
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<tr class="odd">
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<td>Adjustable Gain</td>
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<td>0 to 50</td>
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<td>dB</td>
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</tr>
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<tr class="even">
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<td>Noise Figure (@ 500 MHz)</td>
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<td>9</td>
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<td>dB</td>
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</tr>
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<tr class="odd">
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<td>Central Frequency</td>
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<td>476</td>
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<td>MHz</td>
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</tr>
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<tr class="even">
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<td>Crosstalk</td>
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<td><-50</td>
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<td>dB</td>
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</tr>
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<tr class="odd">
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<td>Bandwidth (3dB)</td>
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<td>25</td>
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<td>MHz</td>
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</tr>
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<tr class="even">
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<td>0.01 dB Compression Point</td>
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<td>>-10</td>
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<td>dBm</td>
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</tr>
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<tr class="odd">
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<td>Long Term Stability</td>
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<td><2E-3</td>
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<td>dB</td>
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</tr>
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</tbody>
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</table>
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| **Parameter**| **Value**| **Unit**|
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| Dynamic Range | 40 | dB |
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| Noise Figure (@ 500 MHz) | \<10 | dB |
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| Crosstalk | \<-40 | dB |
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| Bandwidth (3dB) | 80 | MHz |
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| 1 dB Compression Point | \>20 | dBm |
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| MTBF @ 40 oC | \>20 |
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years|\*
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![](/uploads/e07bd75aa41e98bc80ee59ce981f01be/RFFE_v2_-_Assembled_board.jpg)
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\*MTBF estimation based on MILD-HDBK-217
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### Files
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