[WM][C#][Google Map之基地台定位]

2009-08-09

26659
0
2009-08-10

如果你手上還有一支Windows Mobile 平台手機可是你想要做地圖定位資訊系統，不過機器裡面沒有GPS模組怎麼辦?沒關係這時我們可以利用基地台的id值來做定位，Cell-ID 是全球使用的識別碼，每個基地台都有一個唯一的ID，地區識別碼Location Area Identity(LAI)以及基地台識別碼Cell Identity(CI)，完整的Cell-ID 包含MCC(Mobile Country Code) + MNC(Mobile Network Code) + LAC + CI。通常使用Cell-ID定位的精確度很低，誤差距離大小視基地台的涵蓋半徑而定，大約500 公尺至3 公里，接著我們把取得 Cell ID 值透過 Google Geolocation API 回傳地理經緯度資訊，在把這個這個經緯度到丟到 Google Maps API Services 回傳一張目前的靜態定位圖。

Step1:利用Radio Interface Layer (RIL)提供了一個處理CellCore系統軟體以及無線電硬體之間通訊的介面來取得Cell ID，若想要知道更多的應用函式可以連到 http://msdn.microsoft.com/en-us/library/aa921525.aspx 。接著填入我們的 RIL 程式碼

public class RIL

{

// string used to store the CellID string

private static string celltowerinfo = "";

* Uses RIL to get CellID from the phone.

public static string GetCellTowerInfo()

{

// initialise handles

IntPtr hRil = IntPtr.Zero;

IntPtr hRes = IntPtr.Zero;

// initialise result

celltowerinfo = "";

// initialise RIL

hRes = RIL_Initialize(1, // RIL port 1

new RILRESULTCALLBACK(rilResultCallback), // function to call with result

null, // function to call with notify

0, // classes of notification to enable

0, // RIL parameters

out hRil); // RIL handle returned

if (hRes != IntPtr.Zero)

{

return "Failed to initialize RIL";

}

// initialised successfully

// use RIL to get cell tower info with the RIL handle just created

hRes = RIL_GetCellTowerInfo(hRil);

// wait for cell tower info to be returned

waithandle.WaitOne();

// finished - release the RIL handle

RIL_Deinitialize(hRil);

// return the result from GetCellTowerInfo

return celltowerinfo;

}

// event used to notify user function that a response has

// been received from RIL

private static AutoResetEvent waithandle = new AutoResetEvent(false);

public static void rilResultCallback(uint dwCode,

IntPtr hrCmdID,

IntPtr lpData,

uint cbData,

uint dwParam)

{

// create empty structure to store cell tower info in

RILCELLTOWERINFO rilCellTowerInfo = new RILCELLTOWERINFO();

// copy result returned from RIL into structure

Marshal.PtrToStructure(lpData, rilCellTowerInfo);

// get the bits out of the RIL cell tower response that we want

celltowerinfo = rilCellTowerInfo.dwCellID + "-" +

rilCellTowerInfo.dwLocationAreaCode + "-" +

rilCellTowerInfo.dwMobileCountryCode;

// notify caller function that we have a result

waithandle.Set();

}

// -------------------------------------------------------------------

// RIL function definitions

// -------------------------------------------------------------------

* Function definition converted from the definition

* RILRESULTCALLBACK from MSDN:

* http://msdn2.microsoft.com/en-us/library/aa920069.aspx

public delegate void RILRESULTCALLBACK(uint dwCode,

IntPtr hrCmdID,

IntPtr lpData,

uint cbData,

uint dwParam);

* Function definition converted from the definition

* RILNOTIFYCALLBACK from MSDN:

* http://msdn2.microsoft.com/en-us/library/aa922465.aspx

public delegate void RILNOTIFYCALLBACK(uint dwCode,

IntPtr lpData,

uint cbData,

uint dwParam);

* Class definition converted from the struct definition

* RILCELLTOWERINFO from MSDN:

* http://msdn2.microsoft.com/en-us/library/aa921533.aspx

public class RILCELLTOWERINFO

{

public uint cbSize;

public uint dwParams;

public uint dwMobileCountryCode;

public uint dwMobileNetworkCode;

public uint dwLocationAreaCode;

public uint dwCellID;

public uint dwBaseStationID;

public uint dwBroadcastControlChannel;

public uint dwRxLevel;

public uint dwRxLevelFull;

public uint dwRxLevelSub;

public uint dwRxQuality;

public uint dwRxQualityFull;

public uint dwRxQualitySub;

public uint dwIdleTimeSlot;

public uint dwTimingAdvance;

public uint dwGPRSCellID;

public uint dwGPRSBaseStationID;

public uint dwNumBCCH;

}

// -------------------------------------------------------------------

// RIL DLL functions

// -------------------------------------------------------------------

/* Definition from: http://msdn2.microsoft.com/en-us/library/aa919106.aspx */

[DllImport("ril.dll")]

private static extern IntPtr RIL_Initialize(uint dwIndex,

RILRESULTCALLBACK pfnResult,

RILNOTIFYCALLBACK pfnNotify,

uint dwNotificationClasses,

uint dwParam,

out IntPtr lphRil);

/* Definition from: http://msdn2.microsoft.com/en-us/library/aa923065.aspx */

[DllImport("ril.dll")]

private static extern IntPtr RIL_GetCellTowerInfo(IntPtr hRil);

/* Definition from: http://msdn2.microsoft.com/en-us/library/aa919624.aspx */

[DllImport("ril.dll")]

private static extern IntPtr RIL_Deinitialize(IntPtr hRil);

}

Step2: 將得到 Cell ID 利用 http post 方式傳到 Google 網站轉換成經緯度資訊，可以連到 http://code.google.com/intl/zh-TW/apis/gears/api_geolocation.html 了解運作流程。

class GMM

{

static byte[] PostData(int MCC, int MNC, int LAC, int CID,

bool shortCID)

{

/* The shortCID parameter follows heuristic experiences:

* Sometimes UMTS CIDs are build up from the original GSM CID (lower 4 hex digits)

* and the RNC-ID left shifted into the upper 4 digits.

byte[] pd = new byte[] {

0x00, 0x0e,

0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,

0x00, 0x00,

0x1b,

0x00, 0x00, 0x00, 0x00, // Offset 0x11

0x00, 0x00, 0x00, 0x00, // Offset 0x15

0x00, 0x00, 0x00, 0x00, // Offset 0x19

0x00, 0x00,

0x00, 0x00, 0x00, 0x00, // Offset 0x1f

0x00, 0x00, 0x00, 0x00, // Offset 0x23

0x00, 0x00, 0x00, 0x00, // Offset 0x27

0x00, 0x00, 0x00, 0x00, // Offset 0x2b

0xff, 0xff, 0xff, 0xff,

0x00, 0x00, 0x00, 0x00

};

bool isUMTSCell = ((Int64)CID > 65535);

if (isUMTSCell)

Console.WriteLine("UMTS CID. {0}", shortCID ?

class GMM

{

static byte[] PostData(int MCC, int MNC, int LAC, int CID,

bool shortCID)

{

/* The shortCID parameter follows heuristic experiences:

* Sometimes UMTS CIDs are build up from the original GSM CID (lower 4 hex digits)

* and the RNC-ID left shifted into the upper 4 digits.

byte[] pd = new byte[] {

0x00, 0x0e,

0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,

0x00, 0x00,

0x1b,

0x00, 0x00, 0x00, 0x00, // Offset 0x11

0x00, 0x00, 0x00, 0x00, // Offset 0x15

0x00, 0x00, 0x00, 0x00, // Offset 0x19

0x00, 0x00,

0x00, 0x00, 0x00, 0x00, // Offset 0x1f

0x00, 0x00, 0x00, 0x00, // Offset 0x23

0x00, 0x00, 0x00, 0x00, // Offset 0x27

0x00, 0x00, 0x00, 0x00, // Offset 0x2b

0xff, 0xff, 0xff, 0xff,

0x00, 0x00, 0x00, 0x00

};

bool isUMTSCell = ((Int64)CID > 65535);

if (isUMTSCell)

Console.WriteLine("UMTS CID. {0}", shortCID ?

Using short CID to resolve." : "");

else

Console.WriteLine("GSM CID given.");

if (shortCID)

CID &= 0xFFFF; /* Attempt to resolve the cell using the

if ((Int64)CID > 65536) /* GSM: 4 hex digits, UTMS: 6 hex

digits */

pd[0x1c] = 5;

else

pd[0x1c] = 3;

pd[0x11] = (byte)((MNC >> 24) & 0xFF);

pd[0x12] = (byte)((MNC >> 16) & 0xFF);

pd[0x13] = (byte)((MNC >> 8) & 0xFF);

pd[0x14] = (byte)((MNC >> 0) & 0xFF);

pd[0x15] = (byte)((MCC >> 24) & 0xFF);

pd[0x16] = (byte)((MCC >> 16) & 0xFF);

pd[0x17] = (byte)((MCC >> 8) & 0xFF);

pd[0x18] = (byte)((MCC >> 0) & 0xFF);

pd[0x27] = (byte)((MNC >> 24) & 0xFF);

pd[0x28] = (byte)((MNC >> 16) & 0xFF);

pd[0x29] = (byte)((MNC >> 8) & 0xFF);

pd[0x2a] = (byte)((MNC >> 0) & 0xFF);

pd[0x2b] = (byte)((MCC >> 24) & 0xFF);

pd[0x2c] = (byte)((MCC >> 16) & 0xFF);

pd[0x2d] = (byte)((MCC >> 8) & 0xFF);

pd[0x2e] = (byte)((MCC >> 0) & 0xFF);

pd[0x1f] = (byte)((CID >> 24) & 0xFF);

pd[0x20] = (byte)((CID >> 16) & 0xFF);

pd[0x21] = (byte)((CID >> 8) & 0xFF);

pd[0x22] = (byte)((CID >> 0) & 0xFF);

pd[0x23] = (byte)((LAC >> 24) & 0xFF);

pd[0x24] = (byte)((LAC >> 16) & 0xFF);

pd[0x25] = (byte)((LAC >> 8) & 0xFF);

pd[0x26] = (byte)((LAC >> 0) & 0xFF);

return pd;

}

GSM CID part */

static public string GetLatLng(string[] args)

{

if (args.Length < 4)

{

return string.Empty;

}

string shortCID = ""; /* Default, no change at all */

if (args.Length == 5)

shortCID = args[4].ToLower();

try

{

String url = "http://www.google.com/glm/mmap";

HttpWebRequest req = (HttpWebRequest)WebRequest.Create(

new Uri(url));

req.Method = "POST";

int MCC = Convert.ToInt32(args[0]);

int MNC = Convert.ToInt32(args[1]);

int LAC = Convert.ToInt32(args[2]);

int CID = Convert.ToInt32(args[3]);

byte[] pd = PostData(MCC, MNC, LAC, CID,

shortCID == "shortcid");

req.ContentLength = pd.Length;

req.ContentType = "application/binary";

Stream outputStream = req.GetRequestStream();

outputStream.Write(pd, 0, pd.Length);

outputStream.Close();

HttpWebResponse res = (HttpWebResponse)req.GetResponse();

byte[] ps = new byte[res.ContentLength];

int totalBytesRead = 0;

while (totalBytesRead < ps.Length)

{

totalBytesRead += res.GetResponseStream().Read(

ps, totalBytesRead, ps.Length - totalBytesRead);

}

if (res.StatusCode == HttpStatusCode.OK)

{

short opcode1 = (short)(ps[0] << 8 | ps[1]);

byte opcode2 = ps[2];

int ret_code = (int)((ps[3] << 24) | (ps[4] << 16) |

(ps[5] << 8) | (ps[6]));

if (ret_code == 0)

{

double lat = ((double)((ps[7] << 24) | (ps[8] << 16)

| (ps[9] << 8) | (ps[10]))) / 1000000;

double lon = ((double)((ps[11] << 24) | (ps[12] <<

16) | (ps[13] << 8) | (ps[14]))) /

1000000;

return lat + "|" + lon;

}

else

return string.Empty;

}

else

return string.Empty;

}

catch (Exception ex)

{

MessageBox.Show(ex.ToString());

return string.Empty;

}

Step4:把 Google 回傳的經緯度資訊，在次使用 http 方式傳到 Google 回傳一張靜態定位圖回來，使用方法可連到 http://code.google.com/intl/zh-TW/apis/maps/documentation/staticmaps/ 介紹。

範例: http://maps.google.com/staticmap?&maptype=mobile&key=xxx&markers=25.033875,121.56445&center=,&size=240x320&zoom=15

利用http格式串一個url連線字串回傳一個手機模式的靜態圖，此張圖的尺寸大小為240*320，放大層級到15。

Step4:開啟vs2008新增一個 c# 智慧型裝置專案，在表單上建立webBrowser 元件用來顯示定位圖，在左下方功能表上新增一個map 按鍵用來觸發定位

Step5:在Map按鍵插入下列程式碼

string[] cellidFields =RIL.GetCellTowerInfo().ToString().Split('-');

// [0] - CID

// [1] - LAC

// [2] – MCC

//---Arguments for GetLatLng(MCC MNC LAC CID)---

string[] args = {

cellidFields[2], // MCC

"0", // MNC – don’t need it here

cellidFields[1], // LAC

cellidFields[0] // CID

};

string[] latlng = GMM.GetLatLng(args).Split('|');

Uri url = new Uri("http://maps.google.com/staticmap?&maptype=mobile&key=xxx&markers="+latlng[0].ToString().Replace(',', '.') +","+ latlng[1].ToString().Replace(',', '.') +"&center=,&size=240x320&zoom=15");

webBrowser1.Navigate(url);

Step6:在vs2008編輯器上功能表按下偵錯\開始偵錯部署你的應用程式

Step7:按一下Map來看一下結果吧

Step8: 程式源碼

回首頁