衛星的晶片.....SIRF的解釋??

ann530

ann530
個人積分：1分
文章編號：719244

1分

樓主

2005-09-13 11:40

小妹最近在寫一些有關於衛星導航的報告，才了解到自己也對這個字很不熟悉

(((SIRF))這個字困擾了小妹很久了，不曉得板上大大們能不能幫幫忙，有沒有知道哪邊有網頁可以找的到這些資料，或是大大們能幫我解答呢

拜託囉!!

2005-09-13 11:40 發佈

文章關鍵字衛星晶片解釋 SirF

TOM CHENG

TOM CHENG
個人積分：0分
文章編號：719253

0分

2樓

2005-09-13 11:51

SiRF為專業GPS晶片廠,技術水準已經受到國際大廠的肯定....

ann530

ann530
個人積分：1分
文章編號：719281

1分

樓主

2005-09-13 12:13

謝謝這位好心大大的回覆

那再請問一個很蠢的就是Sirf一代.二代.三袋分別是差在哪邊呢??

感謝在麻煩囉

dw

dw
個人積分：10084分
文章編號：719296

10084分

4樓

2005-09-13 12:31

ann530 wrote:
謝謝這位好心大大的回覆
那再請問一個很蠢的就是Sirf一代.二代.三袋分別是差在哪邊呢??
感謝在麻煩囉

基本上差在一、二、三的不同。
而且SiRF不是什麼一、二、三代...每一種晶片都有代號，例如最新的一款晶片叫做SiRFstar III。還有做GPS不是只有SiRF一家。
你都不做功課，想要用一句話得到一連串的答案，你問的簡單，大家也答的含糊。

來！來！來！做功課了！

SiRFstarIIA
The SiRFstarIIA is designed for applications that will benefit from the high performance of SiRF GPS incorporated into a System On Chip that provides system processing and peripheral control and interfaces. The GSP2A provides over 65 MIPS of throughput and is capable of providing all the central processing for many applications. Interfaces include UARTS, vehicle CAN buses, USB, SPI and ATAPI/EIDE. It can also interface to control panels and display units and support audio interfaces for entertainment or voice prompts.

This power and flexibility makes the SiRFstarIIA an ideal central component for automotive telematics products, including emergency and concierge services, road-tolling, security, and low cost navigation and infotainment systems.

The optional SiRFDRive closely coupled dead reckoning system uses in-expensive heading and speed sensors to provide reliable positions in challenging signal environments including urban canyons, tunnels and under foliage. The GPS and dead reckoning measurements are used in the navigation filter to validate and calibrate each other ensuring accurate and continuous navigation in all conditions.”

SiRFstarIIt
SiRFstarIIt makes it easy and economical to add high-performance SiRFstarII technology to systems that are based on many popular processors and operating systems. The SiRFstarIIt solution allows GPS function to be added at minimal cost in components and circuit board area, by sharing the host system's processor and memory resources. The chip set acquires and tracks satellites, then sends raw measurements to the host processor running the SiRFNav software in parallel with the host applications. The SiRFNav software module computes position time and velocity. For enhanced accuracy and navigation reliability, WAAS corrections can be applied to GPS measurements or GPS can be combined with dead reckoning data and processed by SiRFDRive software.

The chip set consists of the GSP2t highly integrated digital chip, GRF2i integrated RF receiver and the SiRFNav software. The two chips are packaged as 9mm 48-pin LQFP packages and require minimal external components thanks to their high level of integration. SiRFNav software is designed for easy porting to host systems.

SiRFstarIIe/LP
If you’re manufacturing or designing a device using GPS with battery power, the SiRFstarIIe/LP provides an innovative way to add location awareness to your product. Drawing only 60mA in full power and 20mA in TricklePower, the SiRFstarIIe/LP is one of the lowest power full-feature GPS chipsets on the market. The chipset also has an ARM CPU with 40 MIPS of total processing power. This can be used as the engine to drive your product reducing component cost by removing the extra CPU.
The SiRFstarIIe/LP family is comprised of the GRF2i/LP low-power front end, the GSP2e/LP highly integrated digital section, and the GSW2 software, which provides a path for new features and continuous GPS improvement.

SiRFstarIII
With its rapid time-to-first-fix and high sensitivity, the SiRFstarIII architecture is designed to meet the rigorous demands of wireless and handheld LBS applications, and provides superior location performance, both indoors and out, for 2G, 2.5G, 3G asynchronous networks.
The SiRFstarIII architecture packs a performance punch, achieving time-to-first-fix of one second for aided starts in outdoor GSM environments and acquiring signals down to -159 dBm. This makes real-time navigation practical, including in many indoor environments, through urban canyons, and under dense foliage. Unlike the lengthy sequential search process of traditional GPS architectures, the SiRFstarIII architecture, with the equivalent of more than 200,000 correlators, enables fast and deep GPS signal search capabilities, resulting in significant improvement over today’s architectures that contain a few hundred to a few thousand correlators.

The SiRFstarIII family is comprised of the GRF3w RF IC, the GSP3f digital section, and the GSW3 software that is API compatible with GSW2 and SiRFLoc.

那些長久以來享有諸多權利的人，忘了這是由許多人犧牲奉獻換來的。

川島和津實

川島和津實
個人積分：298分
文章編號：719309

298分

5樓

2005-09-13 12:44

sirf的晶片在市面上大概有

Sirf I ---- 很久以前的東西,市面上也找不到了,收訊不佳,又貴,所以還沒普及
Sirf II ---- 這是GPS開始普及化的開始,也是GPS大量應用的開始,定位準,但在市區或高樓林立處,比較容易無法定位
Sirf II Xtrac ---- Sirf II 的加強版,只是更新韌體而已,雖然比Sirf II容易定位,但卻容易飄移,也就是看起來不太準
Sirf II Xtrac2 ---- Sirf II最後的韌體版本,解決Sirf Xtrac飄移的問題,不但收訊佳,也不易飄移,已經算是相當成熟的GPS
Sirf III ---- 現在最新的版本,不但感度增強,準度也有相當提升,可以針對微小訊號做處裡,在訊號微弱的地方,也能有很良好的表現

而不會斷訊,定位速度也相當快,是目前最好的GPS晶片

這幾代有啥差別?當然是一代比一代好,大概就這些差別而已,不過這是以USER角度而言,若以詳細技術差異,可參考dw大的資料

ann530

ann530
個人積分：1分
文章編號：719363

1分

樓主

2005-09-13 13:25

版主的教訓，小妹謹記在心

...((不做功課，被罵活該))

可惜我還不能加分，不然我一定幫版大加分囉!!