android系统支持2G和5G，但车机系统应用只支持5G，但是需要测试2.4G的射频
方法如下：
1、adb shell 进去，su 指定root权限，确保热点处于关闭状态
2、开启热点为www99999, 密码为12345678， wpa2的加密协议
cmd wifi start-softap www99999 wpa2 12345678 -b 5
成功后打印：
onStateChanged with state: 11 failure reason: 0
SAP is disabled
onCapabilityChanged SupportedFeatures=623MaximumSupportedClientNumber=8SupportedChannelListIn24g[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]SupportedChannelListIn5g[36, 40, 44, 48, 149, 153, 157, 161, 165, 52, 56, 60, 64, 100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140, 144]SupportedChannelListIn6g[]SupportedChannelListIn60g[]
onStateChanged with state: 12 failure reason: 0
onStateChanged with state: 13 failure reason: 0
SAP is enabled successfully
3、获取热点的ip地址
ifconfig wlan2
wlan2 Link encap:Ethernet HWaddr e2:bd:81:db:80:35 Driver cnss_pci
inet addr:192.168.42.74 Bcast:192.168.42.255 Mask:255.255.255.0