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GPS的內容

GPS (Global Positioning System)是一個衛星定位系統,使用31個衛星。

GPS 類似 "人造衛星" ,以公尺為計算單位。某些形態的GPS,可以較公分為佳的單位進行度量。

利用先進的科技,從IC及其它的元件中接收訊號。

它大量的降低了成本。

因為它大量降低成本的特性,它可以輕鬆的被整合到手機、筆記型電腦及像是耕作用具、瀏覽系統及建築物...等傳統工具中。tion systems and construction equipment.

(你可以在這個位址Global Positioning System Overview取得其它的相關資訊。)

AGPS

這個分類中可以找到所有GPS的資訊.

PMB 2520 Hammerhead

PMB 2520 Hammerhead是GPS的one-chip解決方案,它由全球定位公司的Infineon Technologies所製造。它允許支援A-GPS標準的資料存取。 (相關的資料都可以在 PMB 2520 datasheet中找到) short datasheet

Hammerhead模組

Hammerhead包含了以下的模組:

  • RF front-end with on-chip, high gain and low noise, LNA, I/Q mixers, on-chip polyphase complex IF filter, digitally controlled AGC, and 3-bits ADC for the I and Q paths.
  • Sigma-Delta RF PLL with on-chip PCO and on-chip loop filter.
  • Embedded PLL and NCO for baseband clock generation.
  • Multiple channels digital mixers and parallel correlator engines to enable real time correlation of the PRN code for up to 14 satellites.
  • Post processor including peak detection logic
  • SRAM for storing correlation results

主要界面

Hammerhead整合了三個系列的介面:

  • UART
  • I2C
  • SPI

在Hammerhead的UART是一個full-duplex UART 界面。它被固定在8N1(8 data bits, no parity, 1 stop bit)模式。在GTA01中,主要的處理器透過UART連接到這裡。在Neo1973的所有產品當中,它連接到敘列埠。

主軟體架構

Hammerhead 驅動程式將會以二進位檔的方法載入,它可以像其它的GPS序列埠般,做為 gpsd的介面,輸入如NMEA 資訊。

gps驅動程式目前已可以使用。(之前,它在取得套件二位元檔授權時,有一些問題 [1])

gpsd程式庫提供下列的資訊,做為高階軟體:

  • Position data
  • Library status
  • Time-out and Packet Available

高階軟體傳送下列的訊息到plugin:

  • Assistance data
  • Positioning Commands
  • Configuration Commands

Gpsd 利用以下的部份與系統進行溝通:

  • Communications Drivers
  • System Timer
  • NV storage
  • Log buffer

GTA01上的GPS

在GTA01,主要的處理器是S3C2410。

GTA01上的Hammerhead

在GTA01上,Hammerhead被設定為透過UART連接到主處理器。UART 的資料輸入/輸出在SC2410上連接到UART 1。UART的硬體流量控制則連接到SC2410的UART 2。

Q & A

Q: gpsd支援不同的GPS嗎

  • 在neo無法有其它方法直接接收DGPS 或WAAS/SCCM時,它可以直接從網際網路伺服器上接收串流。
  • It may be possible to generate a global ionospheric model from stationary (charging?) neos that have GPS signal and cheap internet connections. This would enable very precise positions to be generated
  • This could generate positions accurate to well under a metre, compared to (probably) 2-3m without.
  • The gpsd plugin is the place that these corrections would need to be done, as they need to be performed on a per-satellite basis, before generating the position.
  • This is separate from AGPS - AGPS gives information on current satellite position, or computes your position for you. DGPS is a local minute by minute 'ionospheric weather' for your region.

See also Server:A-GPS.

Q: Can someone upload somewhere an strace of the interaction between gpsd, and the hammerhead chip?

  • Ideally this would be requesting a GPS position every second, starting from 'cold', with no AGPS data, for at least half an hour, in an area where the reciever can see the sky.
  • To aid in reverse engineering efforts.
  • A reverse-engineering page has been created: Hammerhead/Protocol

Q: 我可以自GPS上取得NMEA資料嗎

A: 無法直接取得資料。然而,gpsd 程式的'gpspipe',加入 -r 則可以目前的位置,輸出NMEA資料。正確的方法是在程式裡使用libgpsd。

Personal tools



GPS的內容

GPS (Global Positioning System)是一個衛星定位系統,使用31個衛星。

GPS 類似 "人造衛星" ,以公尺為計算單位。某些形態的GPS,可以較公分為佳的單位進行度量。

利用先進的科技,從IC及其它的元件中接收訊號。

它大量的降低了成本。

因為它大量降低成本的特性,它可以輕鬆的被整合到手機、筆記型電腦及像是耕作用具、瀏覽系統及建築物...等傳統工具中。tion systems and construction equipment.

(你可以在這個位址Global Positioning System Overview取得其它的相關資訊。)

AGPS

這個分類中可以找到所有GPS的資訊.

PMB 2520 Hammerhead

PMB 2520 Hammerhead是GPS的one-chip解決方案,它由全球定位公司的Infineon Technologies所製造。它允許支援A-GPS標準的資料存取。 (相關的資料都可以在 PMB 2520 datasheet中找到) short datasheet

Hammerhead模組

Hammerhead包含了以下的模組:

  • RF front-end with on-chip, high gain and low noise, LNA, I/Q mixers, on-chip polyphase complex IF filter, digitally controlled AGC, and 3-bits ADC for the I and Q paths.
  • Sigma-Delta RF PLL with on-chip PCO and on-chip loop filter.
  • Embedded PLL and NCO for baseband clock generation.
  • Multiple channels digital mixers and parallel correlator engines to enable real time correlation of the PRN code for up to 14 satellites.
  • Post processor including peak detection logic
  • SRAM for storing correlation results

主要界面

Hammerhead整合了三個系列的介面:

  • UART
  • I2C
  • SPI

在Hammerhead的UART是一個full-duplex UART 界面。它被固定在8N1(8 data bits, no parity, 1 stop bit)模式。在GTA01中,主要的處理器透過UART連接到這裡。在Neo1973的所有產品當中,它連接到敘列埠。

主軟體架構

Hammerhead 驅動程式將會以二進位檔的方法載入,它可以像其它的GPS序列埠般,做為 gpsd的介面,輸入如NMEA 資訊。

gps驅動程式目前已可以使用。(之前,它在取得套件二位元檔授權時,有一些問題 [1])

gpsd程式庫提供下列的資訊,做為高階軟體:

  • Position data
  • Library status
  • Time-out and Packet Available

高階軟體傳送下列的訊息到plugin:

  • Assistance data
  • Positioning Commands
  • Configuration Commands

Gpsd 利用以下的部份與系統進行溝通:

  • Communications Drivers
  • System Timer
  • NV storage
  • Log buffer

GTA01上的GPS

在GTA01,主要的處理器是S3C2410。

GTA01上的Hammerhead

在GTA01上,Hammerhead被設定為透過UART連接到主處理器。UART 的資料輸入/輸出在SC2410上連接到UART 1。UART的硬體流量控制則連接到SC2410的UART 2。

Q & A

Q: gpsd支援不同的GPS嗎

  • 在neo無法有其它方法直接接收DGPS 或WAAS/SCCM時,它可以直接從網際網路伺服器上接收串流。
  • It may be possible to generate a global ionospheric model from stationary (charging?) neos that have GPS signal and cheap internet connections. This would enable very precise positions to be generated
  • This could generate positions accurate to well under a metre, compared to (probably) 2-3m without.
  • The gpsd plugin is the place that these corrections would need to be done, as they need to be performed on a per-satellite basis, before generating the position.
  • This is separate from AGPS - AGPS gives information on current satellite position, or computes your position for you. DGPS is a local minute by minute 'ionospheric weather' for your region.

See also Server:A-GPS.

Q: Can someone upload somewhere an strace of the interaction between gpsd, and the hammerhead chip?

  • Ideally this would be requesting a GPS position every second, starting from 'cold', with no AGPS data, for at least half an hour, in an area where the reciever can see the sky.
  • To aid in reverse engineering efforts.
  • A reverse-engineering page has been created: Hammerhead/Protocol

Q: 我可以自GPS上取得NMEA資料嗎

A: 無法直接取得資料。然而,gpsd 程式的'gpspipe',加入 -r 則可以目前的位置,輸出NMEA資料。正確的方法是在程式裡使用libgpsd。