Android4G专⽹模块信号的上报过程
最近⼀直在调试Android的4G专⽹模块；⼀个困扰了我很久的问题昨天也解决了；就是4G信号强度是怎么报上来的？怎么在右上⾓通知栏显⽰的？现在也清楚了；
其实只修改reference-ril.c中的⼀个函数就解决问题了，只是牵扯到很多理解性的东西；
static void requestSignalStrength(void *data, size_t datalen, RIL_Token t)函数是上报信号强度的，是上层每隔⼀段时间主动请求下发的函数；注意这个函数中Android4.0（没有validateInput()对信号强度的验证）和Android4.4.3是通过RIL_SignalStrength_v6结构体上报的；framework解析信号强度4G优先解析的是RSRP；ril.h中有注释：RSRP的范围是 * Range: 44 to 140 dBm；注意44信号强度最⼤；140信号强度最⼩；⼏乎所专⽹模块都上报数据不是44~140范围；有的是0~31；有的是0~99；要做相应的转化；不然信号质量格格显⽰不准；
[cpp] view plain copy
1. typedef struct {
2. int signalStrength; /* Valid values are (0-31, 99) as defined in TS 27.007 8.5 */
3. int rsrp; /* The current Reference Signal Receive Power in dBm multipled by -1.
4. <span > * Range: 44 to 140 dBm</span>
5. * INT_MAX: 0x7FFFFFFF denotes invalid value.
6. * Reference: 3GPP TS 36.133 9.1.4 */
7. int rsrq; /* The current Reference Signal Receive Quality in dB multiplied by -1.
8. * Range: 20 to 3 dB.
9. * INT_MAX: 0x7FFFFFFF denotes invalid value.
10. * Reference: 3GPP TS 36.133 9.1.7 */
11. int rssnr; /* The current reference signal signal-to-noise ratio in 0.1 dB units.
12. * Range: -200 to +300 (-200 = -20.0 dB, +300 = 30dB).
13. * INT_MAX : 0x7FFFFFFF denotes invalid value.
14. * Reference: 3GPP TS 36.101 8.1.1 */
15. int cqi; /* The current Channel Quality Indicator.
16. * Range: 0 to 15.
17. * INT_MAX : 0x7FFFFFFF denotes invalid value.
18. * Reference: 3GPP TS 36.101 9.2, 9.3, A.4 */
19. } RIL_LTE_SignalStrength;
[cpp] view plain copy
1. static int SignalStrengthTransform(int Signal)
2. {
3. if(Signal == 99){
4. return 140;
5. }
6.
7. return (Signal*3 - 140)*(-1); //为了RSRP(44~140)的范围这⾥要根据AT+CSQ上报的值做相应的转换；不然信号显⽰不准确;
8.
9. }
[cpp] view plain copy
1. static void requestSignalStrength(void *data, size_t datalen, RIL_Token t)
2. {
3. ATResponse *p_response = NULL;
4. int err;
5. char *line;
6. int count =0;
7. int numofElements;
8. int *response;
9. int out;
10. RIL_SignalStrength_v6 response_v6;
11. int modem_type;
12. modem_type = runtime_3g_port_type();
13. char signal_level[32];
14.
15. if ((HUAWEI_MODEM == modem_type) ||
16. (AMAZON_MODEM == modem_type)){
17. ALOGE("------------------%s@%d---------------------",__func__,__LINE__);
18. /* Huawei EM770W response is in RIL_GW_SignalStrength form */
19. //numofElements=sizeof(RIL_GW_SignalStrength)/sizeof(int);
20. numofElements=sizeof(RIL_SignalStrength_v6)/sizeof(int);
21. }else{
22. ALOGE("------------------%s@%d---------------------",__func__,__LINE__);
23. numofElements=sizeof(RIL_SignalStrength_v6)/sizeof(int);
24. }
25. response = (int *)calloc(numofElements, sizeof(int));
26. if (!response) goto error;
27. //int response[numofElements];
28.
29. if(sUnsolictedCREG_failed) {
30. LOGW("Retry the AT+CREG event report setting");
31. /* Network registration events */
32. err = at_send_command("AT+CREG=2", &p_response);
33.parse error怎么解决
34. /* some handsets -- in tethered mode -- don't support CREG=2 */
35. if (err < 0 || p_response->success == 0) {
36. at_response_free(p_response);
37. err = at_send_command("AT+CREG=1", &p_response);
38. }
39.
40. if (err < 0 || p_response->success == 0) {
41. LOGE("Warning!No network registration events reported");
42. sUnsolictedCREG_failed = 1;
43. }
44. else {
45. sUnsolictedCREG_failed = 0;
45. sUnsolictedCREG_failed = 0;
46. }
47. at_response_free(p_response);
48. }
49.
50. if(sUnsolictedCGREG_failed) {
51. LOGW("Retry the AT+CGREG event report setting");
52. /* GPRS registration events */
53. err = at_send_command("AT+CGREG=1", &p_response);
54. if (err < 0 || p_response->success == 0) {
55. LOGE("Warning!No GPRS registration events reported");
56. sUnsolictedCGREG_failed = 1;
57. }
58. else {
59. sUnsolictedCGREG_failed = 0;
60. }
61.
62. at_response_free(p_response);
63. }
64.
65. err = at_send_command_singleline("AT+CSQ", "+CSQ:", &p_response);
66.
67. if (err < 0 || p_response->success == 0) {
68. RIL_onRequestComplete(t, RIL_E_GENERIC_FAILURE, NULL, 0);
69. goto error;
70. }
71. memset(&response_v6, 0, sizeof(RIL_SignalStrength_v6));
72.
73. line = p_response->p_intermediates->line;
74.
75. err = at_tok_start(&line);
76. if (err < 0) goto error;
77. #if 0
78. for (count =0; count < numofElements; count ++) {
79. err = at_tok_nextint(&line, &(response[count]));
80. if (err < 0) goto error;
81. }
82. #else
83. err = at_tok_nextint(&line, &out);
84.
85. <span >response_v6.LTE_SignalStrength.rsrp = SignalStrengthTransform(out);</span>
86. if (err < 0) goto error;
87. err = at_tok_nextint(&line, &(response_v6.GW_SignalStrength.bitErrorRate));
88. if (err < 0) goto error;
89. #if 1
90. response_v6.GW_SignalStrength.signalStrength = 99;
91. response_v6.GW_SignalStrength.bitErrorRate = -1;
92. response_v6.CDMA_SignalStrength.dbm = -1;
93. response_v6.io = -1;
94. response_v6.EVDO_SignalStrength.dbm = -1;
95. response_v6.io = -1;
96. response_v6.EVDO_SignalStrength.signalNoiseRatio = -1;
97. response_v6.LTE_SignalStrength.signalStrength = 99;
98. response_v6.LTE_SignalStrength.rsrq = 0x7FFFFFFF;
99. response_v6.LTE_SignalStrength.rssnr = 0x7FFFFFFF;
100. response_v6.LTE_SignalStrength.cqi = 0x7FFFFFFF;
101. #endif
102. #endif
103. ALOGE("------------------%s@%d---------------------
out=%d,signalStrengt=%d,rsrp=%d,bitErrorRate=%d",__func__,__LINE__,out,response_v6.LTE_SignalStrength.signalStrength,response_v6.LTE_SignalStrength.rsrp,response_v6.GW_SignalStrength.bitErro 104.
105. RIL_onRequestComplete(t, RIL_E_SUCCESS, (int *)(&response_v6), sizeof(response_v6));
106.
107. at_response_free(p_response);
108. free(response);
109.
110. //sprintf(signal_level, "link:%d,sig:%d", link_4g, response[0]);
111. //WriteFile("/sdcard/tchtc/4g_", signal_level);
112.
113. return;
114.
115. error:
116. RLOGE("requestSignalStrength must never return an error when radio is on");
117. RIL_onRequestComplete(t, RIL_E_GENERIC_FAILURE, NULL, 0);
118. at_response_free(p_response);
119. free(response);
120.
121. }
信号强度的解析在framework层是通过socket 和rild接⼝通信的；ServiceStateTracker.java⽂件中onSignalStrengthResult(AsyncResult ar, boolean isGsm)会验证ril层上报的信号强度范围是否正确；
[cpp] view plain copy
1. protected boolean onSignalStrengthResult(AsyncResult ar, boolean isGsm) {
2. SignalStrength oldSignalStrength = mSignalStrength;
3.
4. // This signal is used for both voice and data radio signal so parse
5. // all fields
6.
7. if ((ar.exception == null) && (ar.result != null)) {
7. if ((ar.exception == null) && (ar.result != null)) {
8. mSignalStrength = (SignalStrength) ar.result;
9. <span > mSignalStrength.validateInput(); //验证上报的4G信号强度是否在正确范围内?</span>
10. mSignalStrength.setGsm(isGsm);
11. } else {
12. log("onSignalStrengthResult() Exception from RIL : " + ar.exception);
13. mSignalStrength = new SignalStrength(isGsm);
14. }
15.
16. return notifySignalStrength();
17. }
[cpp] view plain copy
1. public void validateInput() {
2. if (DBG) log("Signal before validate=" + this);
3. // TS 27.007 8.5
4. mGsmSignalStrength = mGsmSignalStrength >= 0 ? mGsmSignalStrength : 99;
5. // BER no change;
6.
7. mCdmaDbm = mCdmaDbm > 0 ? -mCdmaDbm : -120;
8. mCdmaEcio = (mCdmaEcio > 0) ? -mCdmaEcio : -160;
9.
10. mEvdoDbm = (mEvdoDbm > 0) ? -mEvdoDbm : -120;
11. mEvdoEcio = (mEvdoEcio >= 0) ? -mEvdoEcio : -1;
12. mEvdoSnr = ((mEvdoSnr > 0) && (mEvdoSnr <= 8)) ? mEvdoSnr : -1;
13.
14. // TS 36.214 Physical Layer Section 5.1.3, TS 36.331 RRC
15. mLteSignalStrength = (mLteSignalStrength >= 0) ? mLteSignalStrength : 99;
16. <span >mLteRsrp = ((mLteRsrp >= 44) && (mLteRsrp <= 140)) ? </span><span >-mLteRsrp</span><span > : SignalStrength.INVALID; //RSR
上报的必须是正数;</span>
17. mLteRsrq = ((mLteRsrq >= 3) && (mLteRsrq <= 20)) ? -mLteRsrq : SignalStrength.INVALID;
18. mLteRssnr = ((mLteRssnr >= -200) && (mLteRssnr <= 300)) ? mLteRssnr
19. : SignalStrength.INVALID;
20. // Cqi no change
21. if (DBG) log("Signal after validate=" + this);
22. }
SignalStrength.Java⽂件中getLevel() 是对信号的解析；4G信号解析就是getLteLevel() 函数；
[cpp] view plain copy
1. public int getLteLevel() {
2. /*
3. * TS 36.214 Physical Layer Section 5.1.3 TS 36.331 RRC RSSI = received
4. * signal + noise RSRP = reference signal dBm RSRQ = quality of signal
5. * dB= Number of Resource blocksxRSRP/RSSI SNR = gain=signal/noise ratio
6. * = -10log P1/P2 dB
7. */
8. int rssiIconLevel = SIGNAL_STRENGTH_NONE_OR_UNKNOWN, rsrpIconLevel = -1, snrIconLevel = -1;
9.
10. if (mLteRsrp > -44) rsrpIconLevel = -1;
11. //根据RSRP信号强度转化成UI通知栏的信号强度格格;
12. else if (mLteRsrp >= -85) rsrpIconLevel = SIGNAL_STRENGTH_GREAT;
13. else if (mLteRsrp >= -95) rsrpIconLevel = SIGNAL_STRENGTH_GOOD;
14. else if (mLteRsrp >= -105) rsrpIconLevel = SIGNAL_STRENGTH_MODERATE;
15. else if (mLteRsrp >= -115) rsrpIconLevel = SIGNAL_STRENGTH_POOR;
16. else if (mLteRsrp >= -140) rsrpIconLevel = SIGNAL_STRENGTH_NONE_OR_UNKNOWN;
17.
18. /*
19. * Values are -200 dB to +300 (SNR*10dB) RS_SNR >= 13.0 dB =>4 bars 4.5
20. * dB <= RS_SNR < 13.0 dB => 3 bars 1.0 dB <= RS_SNR < 4.5 dB => 2 bars
21. * -3.0 dB <= RS_SNR < 1.0 dB 1 bar RS_SNR < -3.0 dB/No Service Antenna
22. * Icon Only
23. */
24. if (mLteRssnr > 300) snrIconLevel = -1;
25. else if (mLteRssnr >= 130) snrIconLevel = SIGNAL_STRENGTH_GREAT;
26. else if (mLteRssnr >= 45) snrIconLevel = SIGNAL_STRENGTH_GOOD;
27. else if (mLteRssnr >= 10) snrIconLevel = SIGNAL_STRENGTH_MODERATE;
28. else if (mLteRssnr >= -30) snrIconLevel = SIGNAL_STRENGTH_POOR;
29. else if (mLteRssnr >= -200)
30. snrIconLevel = SIGNAL_STRENGTH_NONE_OR_UNKNOWN;
31.
32. if (DBG) log("getLTELevel - rsrp:" + mLteRsrp + " snr:" + mLteRssnr + " rsrpIconLevel:"
33. + rsrpIconLevel + " snrIconLevel:" + snrIconLevel);
34.
35. /* Choose a measurement type to use for notification */
36. if (snrIconLevel != -1 && rsrpIconLevel != -1) {
37. /*
38. * The number of bars displayed shall be the smaller of the bars
39. * associated with LTE RSRP and the bars associated with the LTE
40. * RS_SNR
41. */
42. return (rsrpIconLevel < snrIconLevel ? rsrpIconLevel : snrIconLevel);
43. }
44.
45. if (snrIconLevel != -1) return snrIconLevel;
46.
47. if (rsrpIconLevel != -1) return rsrpIconLevel;
47. if (rsrpIconLevel != -1) return rsrpIconLevel;
48.
49. /* Valid values are (0-63, 99) as defined in TS 36.331 */
50. if (mLteSignalStrength > 63) rssiIconLevel = SIGNAL_STRENGTH_NONE_OR_UNKNOWN;
51. else if (mLteSignalStrength >= 12) rssiIconLevel = SIGNAL_STRENGTH_GREAT;
52. else if (mLteSignalStrength >= 8) rssiIconLevel = SIGNAL_STRENGTH_GOOD;
53. else if (mLteSignalStrength >= 5) rssiIconLevel = SIGNAL_STRENGTH_MODERATE;
54. else if (mLteSignalStrength >= 0) rssiIconLevel = SIGNAL_STRENGTH_POOR;
55. if (DBG) log("getLTELevel - rssi:" + mLteSignalStrength + " rssiIconLevel:"
56. + rssiIconLevel);
57. return rssiIconLevel;
58.
59. }
版权声明：本站内容均来自互联网，仅供演示用，请勿用于商业和其他非法用途。如果侵犯了您的权益请与我们联系QQ:729038198，我们将在24小时内删除。
发表评论