Xubuntu16.04系统中安装create_ap创建无线AP：
https://blog.csdn.net/qq_45445740/article/details/133972642?spm=1001.2014.3001.5501
目录
- 1.create_ap.conf 配置文件解析
- 2.关于信号强度和延时
- 2.1 信号强度
- 2.2 信号延时
- 2.3 网络延时测试工具推荐——PingPlotter
- 3.确定当前网卡是否支持5G网络
- 4.通过create_ap修改信道
- 5.坑一：芯片支持5G，网卡不支持
1.create_ap.conf 配置文件解析
/etc/create_ap.conf
CHANNEL=default：无线热点的频道设置为默认信道。
GATEWAY=10.0.0.1：设置无线热点的网关地址为10.0.0.1。
WPA_VERSION=2：设置无线热点使用的WPA版本为2。
ETC_HOSTS=0：禁用/etc/hosts文件的解析。
DHCP_DNS=gateway：设置无线热点的DHCP DNS服务器为网关地址。
NO_DNS=0：启用无线热点的DNS服务器。
NO_DNSMASQ=0：启用DNSMASQ服务。
HIDDEN=0：无线热点的SSID不隐藏。
MAC_FILTER=0：禁用MAC地址过滤。
MAC_FILTER_ACCEPT=/etc/hostapd/hostapd.accept：指定MAC地址过滤的白名单文件路径。
ISOLATE_CLIENTS=0：不隔离连接到无线热点的客户端之间的通信。
SHARE_METHOD=nat：使用NAT方式进行无线热点的Internet共享。
IEEE80211N=0：禁用802.11n标准。（2.4G）
IEEE80211AC=0：禁用802.11ac标准。（5G）
HT_CAPAB=[HT40+]：启用HT40+高级设置。
VHT_CAPAB=：未指定VHT_CAPAB。
DRIVER=nl80211：使用nl80211驱动程序。
NO_VIRT=0：启用虚拟无线接口。
COUNTRY=：未指定国家代码。
FREQ_BAND=2.4：设置频段为2.4GHz。
NEW_MACADDR=：未指定新的MAC地址。
DAEMONIZE=0：不将create_ap进程置于后台运行。
NO_HAVEGED=0：启用haveged服务。
WIFI_IFACE=wlp3s0：指定用于创建无线热点的无线网卡接口。
INTERNET_IFACE=enp1s0：指定用于连接到Internet的有线网卡接口。
SSID=0125：设置无线热点的SSID为0125。
PASSPHRASE=12345678：设置无线热点的密码为12345678。
USE_PSK=0：禁用预共享密钥(PSK)。
2.关于信号强度和延时
2.1 信号强度
推荐测试信号强度的APP
2.2 信号延时
有时候明明信号强度很好，但延时却很高，可能是当前信道的网络较多。
要判断哪个信道不拥堵，可以考虑以下几个因素：
- 信道的使用情况：观察每个信道的使用情况，特别是附近的WIFI网络和其他无线设备。如果某个信道上有多个网络同时使用，那么该信道可能会拥堵。相反，如果某个信道上没有或只有少数网络使用，那么该信道可能不拥堵。
- 信道的干扰情况：除了WIFI网络，还要注意其他可能引起干扰的设备，如蓝牙设备、微波炉等。这些设备可能会占用特定的频段，导致信道拥堵。因此，选择一个与这些设备干扰较少的信道可能更好。
- 信道的频率：不同信道的频率可能会有所不同。一般来说，较高频率的信道可能会有更高的带宽和速度，但在传输距离上可能较短（5G）。因此，如果你的设备距离WIFI路由器较近，可以考虑选择较高频率的信道。
综合考虑以上因素，你可以选择一个较少拥堵、干扰较少且适合你的设备的信道。在给定的信息中，你可以观察每个信道的频率和可能的干扰源，并根据这些信息来判断哪个信道可能不拥堵。
使用iwlist命令来列出无线网卡支持的所有信道：
sudo iwlist wlp3s0 channel
root@bossdog-2177018234:/etc# iwlist wlp3s0 channel
wlp3s0 32 channels in total; available frequencies :
Channel 01 : 2.412 GHz
Channel 02 : 2.417 GHz
Channel 03 : 2.422 GHz
Channel 04 : 2.427 GHz
Channel 05 : 2.432 GHz
Channel 06 : 2.437 GHz
Channel 07 : 2.442 GHz
Channel 08 : 2.447 GHz
Channel 09 : 2.452 GHz
Channel 10 : 2.457 GHz
Channel 11 : 2.462 GHz
Channel 12 : 2.467 GHz
Channel 13 : 2.472 GHz
Channel 36 : 5.18 GHz
Channel 40 : 5.2 GHz
Channel 44 : 5.22 GHz
Channel 48 : 5.24 GHz
Channel 52 : 5.26 GHz
Channel 56 : 5.28 GHz
Channel 60 : 5.3 GHz
Channel 64 : 5.32 GHz
Channel 100 : 5.5 GHz
Channel 104 : 5.52 GHz
Channel 108 : 5.54 GHz
Channel 112 : 5.56 GHz
Channel 116 : 5.58 GHz
Channel 120 : 5.6 GHz
Channel 124 : 5.62 GHz
Channel 128 : 5.64 GHz
Channel 132 : 5.66 GHz
Channel 136 : 5.68 GHz
Channel 140 : 5.7 GHz
2.3 网络延时测试工具推荐——PingPlotter
https://blog.csdn.net/qq_45946755/article/details/104594683
3.确定当前网卡是否支持5G网络
iw reg get
iw list
root@bossdog-2177018234:/etc# iw list
Wiphy phy0
max # scan SSIDs: 20
max scan IEs length: 425 bytes
Retry short limit: 7
Retry long limit: 4
Coverage class: 0 (up to 0m)
Device supports RSN-IBSS.
Device supports AP-side u-APSD.
Device supports T-DLS.
Supported Ciphers:
* WEP40 (00-0f-ac:1)
* WEP104 (00-0f-ac:5)
* TKIP (00-0f-ac:2)
* CCMP (00-0f-ac:4)
* CMAC (00-0f-ac:6)
Available Antennas: TX 0 RX 0
Supported interface modes:
* IBSS
* managed
* AP
* AP/VLAN
* monitor
* P2P-client
* P2P-GO
* P2P-device
Band 1:
Capabilities: 0x11ef
RX LDPC
HT20/HT40
SM Power Save disabled
RX HT20 SGI
RX HT40 SGI
TX STBC
RX STBC 1-stream
Max AMSDU length: 3839 bytes
DSSS/CCK HT40
Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
Minimum RX AMPDU time spacing: 4 usec (0x05)
HT TX/RX MCS rate indexes supported: 0-15
Bitrates (non-HT):
* 1.0 Mbps
* 2.0 Mbps (short preamble supported)
* 5.5 Mbps (short preamble supported)
* 11.0 Mbps (short preamble supported)
* 6.0 Mbps
* 9.0 Mbps
* 12.0 Mbps
* 18.0 Mbps
* 24.0 Mbps
* 36.0 Mbps
* 48.0 Mbps
* 54.0 Mbps
Frequencies:
* 2412 MHz [1] (22.0 dBm)
* 2417 MHz [2] (22.0 dBm)
* 2422 MHz [3] (22.0 dBm)
* 2427 MHz [4] (22.0 dBm)
* 2432 MHz [5] (22.0 dBm)
* 2437 MHz [6] (22.0 dBm)
* 2442 MHz [7] (22.0 dBm)
* 2447 MHz [8] (22.0 dBm)
* 2452 MHz [9] (22.0 dBm)
* 2457 MHz [10] (22.0 dBm)
* 2462 MHz [11] (22.0 dBm)
* 2467 MHz [12] (22.0 dBm) (no IR)
* 2472 MHz [13] (22.0 dBm) (no IR)
Band 2:
Capabilities: 0x11ef
RX LDPC
HT20/HT40
SM Power Save disabled
RX HT20 SGI
RX HT40 SGI
TX STBC
RX STBC 1-stream
Max AMSDU length: 3839 bytes
DSSS/CCK HT40
Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
Minimum RX AMPDU time spacing: 4 usec (0x05)
HT TX/RX MCS rate indexes supported: 0-15
VHT Capabilities (0x038071b0):
Max MPDU length: 3895
Supported Channel Width: neither 160 nor 80+80
RX LDPC
short GI (80 MHz)
TX STBC
SU Beamformee
VHT RX MCS set:
1 streams: MCS 0-9
2 streams: MCS 0-9
3 streams: not supported
4 streams: not supported
5 streams: not supported
6 streams: not supported
7 streams: not supported
8 streams: not supported
VHT RX highest supported: 0 Mbps
VHT TX MCS set:
1 streams: MCS 0-9
2 streams: MCS 0-9
3 streams: not supported
4 streams: not supported
5 streams: not supported
6 streams: not supported
7 streams: not supported
8 streams: not supported
VHT TX highest supported: 0 Mbps
Bitrates (non-HT):
* 6.0 Mbps
* 9.0 Mbps
* 12.0 Mbps
* 18.0 Mbps
* 24.0 Mbps
* 36.0 Mbps
* 48.0 Mbps
* 54.0 Mbps
Frequencies:
* 5180 MHz [36] (22.0 dBm) (no IR)
* 5200 MHz [40] (22.0 dBm) (no IR)
* 5220 MHz [44] (22.0 dBm) (no IR)
* 5240 MHz [48] (22.0 dBm) (no IR)
* 5260 MHz [52] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5280 MHz [56] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5300 MHz [60] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5320 MHz [64] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5500 MHz [100] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5520 MHz [104] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5540 MHz [108] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5560 MHz [112] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5580 MHz [116] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5600 MHz [120] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5620 MHz [124] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5640 MHz [128] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5660 MHz [132] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5680 MHz [136] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5700 MHz [140] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5720 MHz [144] (22.0 dBm) (no IR, radar detection)
DFS state: usable (for 2401 sec)
DFS CAC time: 0 ms
* 5745 MHz [149] (22.0 dBm) (no IR)
* 5765 MHz [153] (22.0 dBm) (no IR)
* 5785 MHz [157] (22.0 dBm) (no IR)
* 5805 MHz [161] (22.0 dBm) (no IR)
* 5825 MHz [165] (22.0 dBm) (no IR)
Supported commands:
* new_interface
* set_interface
* new_key
* start_ap
* new_station
* new_mpath
* set_mesh_config
* set_bss
* authenticate
* associate
* deauthenticate
* disassociate
* join_ibss
* join_mesh
* remain_on_channel
* set_tx_bitrate_mask
* frame
* frame_wait_cancel
* set_wiphy_netns
* set_channel
* set_wds_peer
* tdls_mgmt
* tdls_oper
* start_sched_scan
* probe_client
* set_noack_map
* register_beacons
* start_p2p_device
* set_mcast_rate
* connect
* disconnect
* channel_switch
* Unknown command (104)
* Unknown command (105)
* Unknown command (121)
Supported TX frame types:
* IBSS: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* managed: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* AP: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* AP/VLAN: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* mesh point: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* P2P-client: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* P2P-GO: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
* P2P-device: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
Supported RX frame types:
* IBSS: 0x40 0xb0 0xc0 0xd0
* managed: 0x40 0xd0
* AP: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
* AP/VLAN: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
* mesh point: 0xb0 0xc0 0xd0
* P2P-client: 0x40 0xd0
* P2P-GO: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
* P2P-device: 0x40 0xd0
WoWLAN support:
* wake up on disconnect
* wake up on magic packet
* wake up on pattern match, up to 20 patterns of 16-128 bytes,
maximum packet offset 0 bytes
* can do GTK rekeying
* wake up on GTK rekey failure
* wake up on EAP identity request
* wake up on 4-way handshake
* wake up on rfkill release
* wake up on TCP connection
software interface modes (can always be added):
* AP/VLAN
* monitor
valid interface combinations:
* #{ managed } <= 1, #{ AP, P2P-client, P2P-GO } <= 1, #{ P2P-device } <= 1,
total <= 3, #channels <= 2
HT Capability overrides:
* MCS: ff ff ff ff ff ff ff ff ff ff
* maximum A-MSDU length
* supported channel width
* short GI for 40 MHz
* max A-MPDU length exponent
* min MPDU start spacing
Device supports TX status socket option.
Device supports HT-IBSS.
Device supports SAE with AUTHENTICATE command
Device supports low priority scan.
Device supports scan flush.
Device supports per-vif TX power setting
P2P GO supports CT window setting
P2P GO supports opportunistic powersave setting
Driver supports full state transitions for AP/GO clients
Driver supports a userspace MPM
Driver/device bandwidth changes during BSS lifetime (AP/GO mode)
Device supports static SMPS
Device supports dynamic SMPS
显示， (no IR, radar detection) 就是 这些5G 通道不可用
4.通过create_ap修改信道
修改create_ap.conf中的配置项
CHANNEL=8：无线热点的频道设置为信道8。
FREQ_BAND=2.4：设置频段为2.4GHz。
CHANNEL=36：无线热点的频道设置为信道36。
FREQ_BAND=5：设置频段为5GHz。
5.坑一：芯片支持5G，网卡不支持
-
问题：Ubuntu22 can’t create 5G hotspot：
https://askubuntu.com/questions/1484841/ubuntu22-cant-create-5g-hotspot -
问题：Wifi 5GHz AP Mode: What does no IR means and can I bypass it?
https://superuser.com/questions/809282/wifi-5ghz-ap-mode-what-does-no-ir-means-and-can-i-bypass-it -
猜测是驱动不支持，需要更新Linux内核
https://wireless.wiki.kernel.org/en/users/drivers/iwlwifi
https://www.intel.com/content/www/us/en/support/articles/000005511/wireless.html
参考
https://blog.csdn.net/subfate/article/details/51882322
