android 精确定位

原理
通过手机读取附近的手机信号基站id，然后查询google公开的基站数据库获取经纬度。
实现
通过TelephonyManager 获取lac:mcc:mnc:cell-id(请参考sdk doc文档中TelephonyManager api介绍)，发送到http://www.google.com/loc/json 查询。
如果不知道lac, mcc, mnc, cell-id, 请Google。
google location api 详细地址http://code.google.com/p/gears/wiki/GeolocationAPI
代码是以前写的简单的例子(其中函数getNeighboringCellInfo()在android1.5之下是有问题的，返回为空，后者返回无效数据)

package com.test;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.StringWriter;
import java.io.UnsupportedEncodingException;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.telephony.CellLocation;
import android.telephony.NeighboringCellInfo;
import android.telephony.PhoneStateListener;
import android.telephony.TelephonyManager;
import android.telephony.gsm.GsmCellLocation;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class LocationMe extends Activity implements OnClickListener {
        /** Called when the activity is first created. */
        TelephonyManager manager;
        TextView tv,loc;
        int mcc, mnc, lac[] , ci[];
        String mac;
        EditText mcc_text, mnc_text, lac_text, ci_text, mac_text;
        Button find,showinmap,update;
        int count ;
        ProgressDialog mProgressDialog;
        PhoneStateListener  listener;
        
        Handler mHandler  = new Handler(){
                @Override
                public void handleMessage(Message msg) {
                        if(msg.what==100){
                                mProgressDialog.dismiss();
                                lac_text.setText(lac[0]+","+lac[1]);//+","+lac[2]);
                                ci_text.setText(ci[0]+","+ci[1]);//+","+ci[2]);
                        }
                        if(msg.what==101){
                                tv.setText(result_location);
                                loc.setText( la + "-" + lo);
                                showinmap.setEnabled(true);
                                mProgressDialog.dismiss();
                        }
                        if(msg.what==102){
                                mProgressDialog.dismiss();
                        }
                }
        };
        @Override
        public void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.main);
                tv = (TextView) findViewById(R.id.tv);
                loc = (TextView) findViewById(R.id.location);
                mcc_text = (EditText) findViewById(R.id.mcc);
                mnc_text = (EditText) findViewById(R.id.mnc);
                lac_text = (EditText) findViewById(R.id.lac);
                ci_text = (EditText) findViewById(R.id.ci);
                mac_text= (EditText) findViewById(R.id.mac);
                find = (Button) findViewById(R.id.find_btn);
                showinmap = (Button) findViewById(R.id.show_in_map);
                manager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
                update= (Button) findViewById(R.id.update);
                
                find.setOnClickListener(this);
                update.setOnClickListener(this);
                showinmap.setOnClickListener(this);
                
                ci = new int[10];
                lac = new int[10];
                mProgressDialog =new ProgressDialog(this);
                mProgressDialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
                mProgressDialog.setCancelable(false);
                listener = new CellStateListener ();
        }
        void update(){
                count =0;
//                CellLocation location = manager.getCellLocation();
                Log.e("Location","NetworkCountryIso"+manager.getNetworkCountryIso());//cn
                mcc = Integer.valueOf(manager.getNetworkOperator().substring(0,3));
                mcc_text.setText(String.valueOf(mcc));
                mnc = Integer.valueOf(manager.getNetworkOperator().substring(3,5));;
                mnc_text.setText(String.valueOf(mnc));
                
                
                
//                manager.listen(listener, PhoneStateListener.LISTEN_CELL_LOCATION);
                manager.listen(listener, 0);
                GsmCellLocation sm = ((GsmCellLocation)manager.getCellLocation());
                Log.e("Location", "cid"+sm.getCid()+" lac"+sm.getLac());
                lac[0]=sm.getLac();
//                mProgressDialog.setMessage("Updating...(0/3)");
//                mProgressDialog.show();
                List<NeighboringCellInfo> list = manager.getNeighboringCellInfo();
                
                count = list.size();
                Log.e("Location","neighbors "+count);
                NeighboringCellInfo info;
                loc.setText("");
                ci_text.setText("");
                for(int i =0; i<count;i++){
                        info = list.get(i);
                        Log.e("Location", info.getCid()+"-"+info.getRssi()+" "+info.toString());
                        lac=lac[0];
                        ci=info.getCid()-415500000;
                        ci_text.setText(ci_text.getText().toString()+","+ci);
                        loc.setText(loc.getText()+" "+info.getCid());
                }
        }
        void findme() {
                mProgressDialog.setMessage("Finding...");
                mProgressDialog.show();
                Thread thread = new Thread(){
                        public void run(){
                                try {
                                        DefaultHttpClient client = new DefaultHttpClient();

                                        HttpPost post = new HttpPost("http://www.google.com/loc/json");//http://www.google.com/glm/mmap");//
                                        JSONObject holder = new JSONObject();

                                        holder.put("version", "1.1.0");
//                                        holder.put("host", "maps.google.com");
//                                        holder.put("home_mobile_country_code", mcc);
//                                        holder.put("home_mobile_network_code", mnc);
//                                        holder.put("radio_type", "gsm");
//                                        holder.put("carrier", "Vodafone");
                                        holder.put("request_address", true);
                                        holder.put("address_language", "en-us");

                                        JSONObject data ;// = new JSONObject();
//                                         data.put("latitude", 31.244506);
//                                         data.put("longitude", 121.591095);
//                                         holder.put("location",data);
                                        
                                        JSONArray array = new JSONArray();
                                        for(int i =0;i<(count<2 count:2);i++){
                                                data = new JSONObject();
                                                data.put("cell_id", ci);  // 9457, 8321,8243
                                                data.put("location_area_code", lac);// 28602
                                                data.put("mobile_country_code", mcc);// 208
                                                data.put("mobile_network_code", mnc);// 0
                                                data.put("age", 0);
//                                                data.put("signal_strength", -60);
//                                                data.put("timing_advance", 5555);
                        
                                                
                                                array.put(data);
                                        }
                                        holder.put("cell_towers", array);
                                        
                                        ////////////////////////WIFI//////////////////////////////////////
//                                        WifiManager wm = (WifiManager)getSystemService(Context.WIFI_SERVICE);
//                                        WifiInfo info = wm.getConnectionInfo();
//                                        String mac = info.getMacAddress();
//                                        Log.e("LocationMe","mac:"+mac);
//                                        data = new JSONObject();
//                                        data.put("mac_address", mac);
//                                        data.put("signal_strength", 8);
//                                        data.put("age", 0);
//                                        array = new JSONArray();
//                                        array.put(data);
                                        //holder.put("wifi_towers        ", array);
                                        ////////////////////////////////////
                                        
                                        
                                        

                                        StringEntity se = new StringEntity(holder.toString());
                                        Log.e("Location send",holder.toString());
                                        post.setEntity(se);
                                        HttpResponse resp = client.execute(post);

                                        HttpEntity entity = resp.getEntity();

                                        BufferedReader br = new BufferedReader(new InputStreamReader(entity
                                                        .getContent()));
                                        StringBuffer sb = new StringBuffer();
                                        String result = br.readLine();
                                        while (result != null) {
                                                Log.e("Locaiton reseive", result);
                                                sb.append(result);
                                                result = br.readLine();
                                        }
                                        result_location = sb.toString();
                                        
                                        
                                        data = new JSONObject(sb.toString());
                                        data = (JSONObject) data.get("location");
                                        la = (Double) data.get("latitude");
                                        lo = (Double) data.get("longitude");
                                        mHandler.sendEmptyMessage(101);
                                } catch (ClientProtocolException e) {
                                        e.printStackTrace();
                                        mHandler.sendEmptyMessage(102);
                                } catch (IOException e) {
                                        e.printStackTrace();
                                        mHandler.sendEmptyMessage(102);
                                } catch (JSONException e) {
                                        e.printStackTrace();
//                                        loc.setText("");
//                                        showinmap.setEnabled(false);
                                        mHandler.sendEmptyMessage(102);
                                }
                        }
                };
                thread.start();
                
        }
        
        
        String result_location;
        double la,lo;
        @Override
        public void onClick(View arg0) {
                switch(arg0.getId()){
                        case R.id.find_btn:{
                                findme();
                                break;
                        }
                        case R.id.show_in_map:{
                                Uri mapUri = Uri.parse("geo:"+la+","+lo+" z=12&cbp=1");
                                startActivity(new Intent(Intent.ACTION_VIEW, mapUri));
                                break;
                        }
                        case R.id.update:{
                                update();
                                break;
                        }
                                
                }
                
        }
        class CellStateListener extends PhoneStateListener{
                public void onCellLocationChanged(CellLocation location){
                        GsmCellLocation gsmL = (GsmCellLocation) location;
                        if(count <2){
                                ci[count] = gsmL.getCid();
                                lac[count] = gsmL.getLac();
                                count++;
                                mProgressDialog.setMessage("Updating...("+count+"/3)");
                                gsmL.requestLocationUpdate();
                                if(count ==2){
                                        manager.listen(this, 0);
                                        mHandler.sendEmptyMessage(100);
                                }
                        } 
                        
                         
                }
        }
}

/*
Gears Request


{
  "version": "1.1.0",
  "host": "maps.google.com",
  "access_token": "2:k7j3G6LaL6u_lafw:4iXOeOpTh1glSXe",
  "home_mobile_country_code": 310,
  "home_mobile_network_code": 410,
  "radio_type": "gsm",
  "carrier": "Vodafone",
  "request_address": true,
  "address_language": "en_GB",
  "location": {
    "latitude": 51.0,
    "longitude": -0.1
  },
  "cell_towers": [
    {
      "cell_id": 42,
      "location_area_code": 415,
      "mobile_country_code": 310,
      "mobile_network_code": 410,
      "age": 0,
      "signal_strength": -60,
      "timing_advance": 5555
    },
    {
      "cell_id": 88,
      "location_area_code": 415,
      "mobile_country_code": 310,
      "mobile_network_code": 580,
      "age": 0,
      "signal_strength": -70,
      "timing_advance": 7777
    }
  ],
  "wifi_towers": [
    {
      "mac_address": "01-23-45-67-89-ab",
      "signal_strength": 8,
      "age": 0
    },
    {
      "mac_address": "01-23-45-67-89-ac",
      "signal_strength": 4,
      "age": 0
    }
  ]
}


* responce
{
  "location": {
    "latitude": 51.0,
    "longitude": -0.1,
    "altitude": 30.1,
    "accuracy": 1200.4,
    "altitude_accuracy": 10.6,
    "address": {
      "street_number": "100",
      "street": "Amphibian Walkway",
      "postal_code": "94043",
      "city": "Mountain View",
      "county": "Mountain View County",
      "region": "California",
      "country": "United States of America",
      "country_code": "US"
    }
  },
  "access_token": "2:k7j3G6LaL6u_lafw:4iXOeOpTh1glSXe"
}

08-03 16:48:08.393: ERROR/Location(2350): NetworkCountryIsocn
08-03 16:48:08.423: ERROR/Location(2350): cid9457 lac6340
08-03 16:48:08.443: ERROR/Location(2350): neighbors 5
08-03 16:48:08.453: ERROR/Location(2350): 415506483-9 [18c42033 at 9]
08-03 16:48:08.463: ERROR/Location(2350): 415506691-9 [18c42103 at 9]
08-03 16:48:08.463: ERROR/Location(2350): 415506529-7 [18c42061 at 7]
08-03 16:48:08.473: ERROR/Location(2350): 415531363-11 [18c48163 at 11]
08-03 16:48:08.483: ERROR/Location(2350): 415506531-6 [18c42063 at 6]

*
*/

http://hi.baidu.com/adnroidorg/blog/item/96c65dd750a12c16a08bb7eb.html