雙卡雙待手機(jī)有DSDS（Dual?Sim Dual Standby）和DSDA（Dual SIM dual active）方案，早期產(chǎn)品使用DSDA?方案比較多，隨著多模、多頻段、CA、MIMO等技術(shù)出現(xiàn)，硬件射頻復(fù)雜度大大增加，再加上雙卡雙通的實(shí)際使用場(chǎng)景并不多，DSDS就成為了目前市場(chǎng)的主流方案。

DSDS只有一張卡能夠占有PS業(yè)務(wù)?；騌adio resource，故引入了DDS（Default Data?SIM）概念。雙SIM卡手機(jī)，只有一張卡能進(jìn)行數(shù)據(jù)業(yè)務(wù)，稱為主卡，另一張卡則稱為副卡。若進(jìn)行主副卡切換，則副卡切為DDS主卡；

DDS切換流程

手動(dòng)DDS切換

通過setting-雙卡與移動(dòng)網(wǎng)絡(luò)，選擇默認(rèn)上網(wǎng)卡。

DDS狀態(tài)會(huì)保存在telephony的DB中，對(duì)應(yīng)為Settings.Global.MULTI_SIM_DATA_CALL_SUBSCRIPTION。

可通過adb shell getprop settings list multi_sim_data_call進(jìn)行查看。

frameworks/opt/telephony/src/java/com/android/internal/telephony/SubscriptionController.java?????

public void setDefaultDataSubId(int subId) {

enforceModifyPhoneState("setDefaultDataSubId"); ?????????????????????? ? ? ? ? ? ? ? ?? String flexMapSupportType =

SystemProperties.get("persist.radio.flexmap_type", "nw_mode");

if (subId == SubscriptionManager.DEFAULT_SUBSCRIPTION_ID) {

throw new RuntimeException("setDefaultDataSubId called with DEFAULT_SUB_ID");

}

updateAllDataConnectionTrackers();

Settings.Global.putInt(mContext.getContentResolver(),

Settings.Global.MULTI_SIM_DATA_CALL_SUBSCRIPTION, subId);

broadcastDefaultDataSubIdChanged(subId);

} ?

DDS切換Log參考

部分log如下，主要是PS domain/pdp建立。

//Setting UI set DDS

MobileNetworkSettings: Default Data SubId [1]

//telephony-fwk subscription module detect DDS switch

SubscriptionMonitor:?Default changed 1->2

SubscriptionMonitor: newDefaultDataPhoneId=1

SubscriptionMonitor: Default phoneId changed 0->1, 1,1 registrants

TelephonyNetworkFactory[0]: onDefaultChange(true,false)

TelephonyNetworkFactory[1]: onDefaultChange(false,true)

//set PS domain switch cmd to RIL

PhoneSwitcher: InformDdsToRil rild= 1, DDS=1?RILJ ???: [4184]> RIL_REQUEST_ALLOW_DATA allowed: false [SUB0]

RILJ ???: [4185]> RIL_REQUEST_ALLOW_DATA allowed: true [SUB1]

RILJ ???: [4184]< RIL_REQUEST_ALLOW_DATA ?[SUB0]

RILJ ???: [4185]< RIL_REQUEST_ALLOW_DATA ?[SUB1]

//PS domain camp on

QtiGsmDCT: [1]onDataConnectionAttached

//try setup pdp

TelephonyNetworkFactory[1]: onActivePhoneSwitch(true, true)

TelephonyNetworkFactory[1]: onReleaseNetworkFor NetworkRequest [ id=8, legacyType=-1, [ Transports: CELLULAR Capabilities: IMS&TRUSTED&NOT_VPN] ]

TelephonyNetworkFactory[0]: not releasing - isApp=false, isAct=false NetworkRequest [ id=8, legacyType=-1, [ Transports: CELLULAR Capabilities: IMS&TRUSTED&NOT_VPN] ]

RILJ ???: [4260]> SETUP_DATA_CALL 14 0 cmnet ??0 IPV4V6 [SUB1]

RILJ ???: [4260]< SETUP_DATA_CALL DataCallResponse: {version=11 status=0 retry=-1 cid=0 active=2 type=IPV4V6 ifname=rmnet_data0 mtu=1500 addresses=[10.148.243.195/29] dnses=[211.136.112.50,211.136.150.66] gateways=[10.148.243.196] pcscf=[]} [SUB1]

TelephonyNetworkFactory[1]: got request NetworkRequest [ id=10, legacyType=-1, [ Transports: CELLULAR Capabilities: IMS&TRUSTED&NOT_VPN] ] with score 0

TelephonyNetworkFactory[0]: got request NetworkRequest [ id=10, legacyType=-1, [ Transports: CELLULAR Capabilities: IMS&TRUSTED&NOT_VPN] ] with score 0

TelephonyNetworkFactory[1]: onNeedNetworkFor NetworkRequest [ id=10, legacyType=-1, [ Transports: CELLULAR Capabilities: IMS&TRUSTED&NOT_VPN] ]

TelephonyNetworkFactory[0]: not acting - isApp=false, isAct=false NetworkRequest [ id=10, legacyType=-1, [ Transports: CELLULAR Capabilities: IMS&TRUSTED&NOT_VPN] ]

RILJ ???: [4279]> SETUP_DATA_CALL 14 2 ims ??0 IPV4V6 [SUB1]

RILJ ???: [4279]< SETUP_DATA_CALL DataCallResponse: {version=11 status=0 retry=-1 cid=1 active=2 type=IPV4V6 ifname=rmnet_data7 mtu=1500 addresses=[2409:8804:8010:17cc:db16:6730:30b2:383c/64] dnses=[] gateways=[fe80:0000:0000:0000:e1cc:541a:ab8c:f1bf] pcscf=[]} [SUB1]

動(dòng)態(tài)DDS切換

除了用戶手動(dòng)設(shè)置DDS外，特定的場(chǎng)景還可以進(jìn)行DDS動(dòng)態(tài)切換。

當(dāng)subInfo/network request/radio state/數(shù)據(jù)開關(guān)/通話狀態(tài)等改變時(shí)，都會(huì)觸發(fā)onEvaluate方法，判斷當(dāng)前應(yīng)該將DDS切換到哪張卡上。

當(dāng)然，動(dòng)態(tài)DDS切換的場(chǎng)景還有很多，例如信號(hào)強(qiáng)度、網(wǎng)絡(luò)注冊(cè)狀態(tài)、吞吐量等等，手機(jī)廠家可以使用更優(yōu)的算法進(jìn)行更智能化切換，讓數(shù)據(jù)建立在性能更優(yōu)的SIM卡上，滿足用戶的流暢體驗(yàn)。?文章來源地址http://www.zghlxwxcb.cn/news/detail-492382.html

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