手机在lte only 没有"hd"标志，上网正常，看不到ims注删信令

log ：

[0xB0ED] | OTA LOG | 2017/03/30 06:22:49.000 | LTE NAS EMM Plain OTA Outgoing Message | 

UE_usage_setting = 0 (0x0) (Voice centric)

voice_domain_pref_for_EUTRAN = 3 (0x3) (IMS PS Voice preferred, CS Voice as secondary)

[0xB0EC] | OTA LOG | 2017/03/30 06:22:49.239 | LTE NAS EMM Plain OTA Incoming Message | Attach accept Msg |  | 

 IMSVoPS = 0 (0x0) (IMS Vo PS Session in S1 Mode not supported)

手机在global模式下，有"hd"标志，上网正常，volte正常，能看到ims注删信令

[0xB0ED] | OTA LOG | 2017/03/30 06:27:03.603 | LTE NAS EMM Plain OTA Outgoing Message | Attach request Msg |  | 

UE_usage_setting = 0 (0x0) (Voice centric)

voice_domain_pref_for_EUTRAN = 3 (0x3) (IMS PS Voice preferred, CS Voice as secondary)

[0xB0EC] | OTA LOG | 2017/03/30 06:27:04.040 | LTE NAS EMM Plain OTA Incoming Message | Attach accept Msg |  | 

IMSVoPS = 1 (0x1) (IMS Vo PS Session in S1 Mode supported)

这是网络限制，还是终端的bug

上海同个版本手机正常。两种模式下。

支持VOLTE通话时，终端需开启“数据+语音”模式；各品牌的操作方式可能不同，你可看一下说明。。