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en:uhf_tx_subsys [2017/12/03 15:47]
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en:uhf_tx_subsys [2018/01/23 18:14]
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 {{ ru:​device_standart.jpg?​direct&​200|}} {{ ru:​device_standart.jpg?​direct&​200|}}
-The spacecraft telemetry transmitter is most often a VHF transmitter operating at 145 or 436 MHz range providing a low speed data transmission ​with an omnidirectional or near-omnidirectional ​onboard ​antenna. A high transfer speed is not needed herethe amount of telemetry information from the device is usually much lower than the data stream ​from the payload for which this satellite was launched into space. ​Another point is if there are problems on board and if the device ​can lose its orientation,​ this communication channel ​remains ​available in order to obtain critical information about the state of the on-board service systems and restore the satellite'​s operability.+The spacecraft telemetry transmitter is most often a VHF transmitter operating at either the 145 or 436 MHz range and providing a low data rate with an omnidirectional or near-omnidirectional ​on-board ​antenna. A high data rate is not needed here as the amount of telemetry information from the device is usually much lower than the data rate from the payload for which this satellite was launched into space. ​Additionally, ​if there are problems on-board and if the device ​loses its orientation,​ this communication channel ​will remain ​available in order to obtain critical information about the state of the on-board service systems and restore the satellite'​s operability.
  
-In case of abnormal work of the board any information is extremely important. ​It allows the operational control group, who is on duty at the Control Center ​and works with the satellite in communication sessionsto identify problemsto take some decisions on its solvingThe low-speed communication channel consumes a small amount of [[power_subsys|energy]] in comparison with the [[hf_tx_subsys|HF radio channel]].+In case of board abnormalities, ​any and all information is extremely important. ​The information ​allows the operational control group that is on duty at the MCC and working ​with the satellite in communication sessions to identify problems ​and decide how to solve those problemsIn this case, the low-speed communication channel consumes a small amount of [[power_subsys|energy]] in comparison with the [[hf_tx_subsys|HF radio channel]].
  
-As part of the construction set, the VHF radio channel is implemented in the form of two modules: the on-board transmitter module and [[uhf_rx_subsys|the ground receiver module]]. Data transfer to the ground is carried out using the function: \\ +As part of the construction set, the VHF radio channel is implemented in the form of two modules: the on-board transmitter module and [[uhf_rx_subsys|the ground receiver module]]. Data transfer to the ground is carried out using the following ​function: \\ 
   int32_t transceiver_send(uint16_t tx_num,​uint16_t rx_num,​const uint8_t *data,​uint16_t len);    int32_t transceiver_send(uint16_t tx_num,​uint16_t rx_num,​const uint8_t *data,​uint16_t len); 
-At the same time, under the experimental conditions the transmitter has the number "​2"​ (marked on the body), and [[uhf_rx_subsys|the receiver (ground)]] is number "​1"​. The array of data transmitted from the board to the Earth is a byte array of random ​length and composition that can be transmitted to [[sim_earth|the Earth]] indicating its length. On Earth, messages received during a communication session are displayed in real time in the MCC software interface "​as ​it is", so it is most advantageous to transmit telemetry in text form.+Under the experimental conditions the transmitter has the number "​2"​ (marked on the body), and [[uhf_rx_subsys|the receiver (ground)]] is number "​1"​. The array of data transmitted from the board to the Earth is a byte array of arbitrary ​length and composition that can be transmitted to [[sim_earth|the Earth]]indicating its length. On Earth, messages received during a communication session are displayed in real time in the MCC software interface "as is," ​so it is most advantageous to transmit telemetry in text form.
  
en/uhf_tx_subsys.txt · Last modified: 2019/09/16 15:46 by golikov