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Data logging system for optical, satellite, Bluetooth

Short answer

Optical receiver uses photodiode and amplifier; satellite receiver uses dish, LNB, down-converter, and demodulator; Bluetooth uses 2.4 GHz GFSK receiver. All three digital streams are interfaced to a microcontroller that time-stamps, error-checks, and stores data in flash memory, accessible via PC link.

Design a data logging and storage system that is capable of receiving and storing signals from optical fibers, satellites and Bluetooth devices. Provide the block diagram of the overall system, which should show how messages get transmitted over the three transmission schemes and how the logger receives them.

The logger needs three receiving front ends (optical fibre, satellite, Bluetooth) feeding a common processing and storage unit.

 OPTICAL FIBRE
 Sensor/Data -> E/O (LED/laser) ==fibre==> O/E (photodiode+amp) --+
 SATELLITE                                                        |
 Data -> Modulator -> Up-converter -> HPA -> Dish ~~> Satellite   |
 Satellite ~~> Dish+LNB -> Down-converter -> Demodulator ---------+
 BLUETOOTH                                                        |
 Device -> BT radio ~~~ 2.4 GHz ~~~> BT receiver (antenna, GFSK demod) -+
                                                                  v
                  +---------------------------------------------------+
                  | Interface / multiplexer -> Microcontroller (decode, |
                  |   time-stamp, error check) -> Memory (flash/disk)  |
                  +-------------------------+-------------------------+
                              Display, PC / network link, power supply
  • Optical fibre: an LED or laser converts the electrical data into light pulses; the logger receives with a photodiode and a transimpedance amplifier and regenerates the bits.
  • Satellite: the earth station modulates, up-converts and transmits to the satellite; the logger has a dish, LNB, down-converter and demodulator that recover the data.
  • Bluetooth: short-range 2.4 GHz radio; the logger's Bluetooth receiver recovers packets.
  • Each front end gives digital data to the controller via a serial interface (UART/SPI); the controller identifies the source, checks errors (CRC), time-stamps and stores to non-volatile memory, and gives data to the PC.

✓ Answer checked by Claude Sonnet 5.5

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