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history [2026/10/09 12:42] – pkovarhistory [2026/10/09 12:46] (current) – pkovar
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   * **2016: Introduction to the market** - GPS L1 C/A receiver with the 15 GPS L1 E-L correlators. Serial acquisition based on N of M algorithm. The typical receiver's start time in ideal conditions was 300 seconds.   * **2016: Introduction to the market** - GPS L1 C/A receiver with the 15 GPS L1 E-L correlators. Serial acquisition based on N of M algorithm. The typical receiver's start time in ideal conditions was 300 seconds.
  
-  * **2017: Acquisition unit ** The problem of the pNav receiver from the beginning till the introduction of pNav2 is a problematic cold start and restart after position loss. The partial solution was the introduction of the DSP acquisition unit, which can investigate the entire search range in Doppler frequency and code delay for all 32 satellites within 20 seconds. Unfortunately, due to the hardware manufacturer's technological limitations, we could not use an FPGA with sufficient performance to run GPS correlators and an acquisition unit simultaneously. So the receiver first configures the FPGA with an acquisition unit. After it finishes the signal processing, the FPGA is reprogrammed by a GPS correlators. The information from the acquisition unit is used for the acceleration of the receiver cold start. Under the ideal conditions, the receiver's cold start was shortened to 60 - 70 seconds. But this receiver configuration does not allow the DSP requisition if the signal or position is lost! +  * **2017: Acquisition unit ** From its inception until the introduction of pNav2, one of the main limitations of the pNav receiver was its slow cold start and position reacquisition. The partial solution was the introduction of the DSP acquisition unit, which can investigate the entire search range in Doppler frequency and code delay for all 32 satellites within 20 seconds. Unfortunately, due to the hardware manufacturer's technological limitations, we could not use an FPGA with sufficient performance to run GPS correlators and an acquisition unit simultaneously. So the receiver first configures the FPGA with an acquisition unit. After it finishes the signal processing, the FPGA is reconfigured to run a GPS correlators. The information from the acquisition unit is used for the acceleration of the receiver cold start. Under the ideal conditions, the receiver's cold start was shortened to 60 - 70 seconds. But this receiver configuration does not allow the DSP requisition if the signal or position is lost! 
      
   * **2018: Buying and implementation of a GPS software simulator ReGen** by IPSolutions.   * **2018: Buying and implementation of a GPS software simulator ReGen** by IPSolutions.
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   * Increasing the robustness of the software. Consistent verification of the navigation message reception with the aim of detecting undetected errors through channel coding. Verification of the position input and output data and proper function of the position, velocity, and time algorithm.   * Increasing the robustness of the software. Consistent verification of the navigation message reception with the aim of detecting undetected errors through channel coding. Verification of the position input and output data and proper function of the position, velocity, and time algorithm.
   * Development of the high-performance, low-power consumption GPS antenna suitable for CubeSats.   * Development of the high-performance, low-power consumption GPS antenna suitable for CubeSats.
-  * Reliable positioning of the unstabilized, rotating, or spinning satellites. +  * Reliable positioning of unstabilized, rotating, or spinning satellites. 
  
  
history.1791542570.txt.gz · Last modified: by pkovar

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