for*_*kle 6 linux wireless-networking dual-band wifi-driver wifi-configuration
如果我iw reg get在我的系统（Ubuntu 16.04.4 LTS，内核 4.13，iw版本 3.17）中运行命令，我会得到以下输出：
country PT: DFS-ETSI
(2402 - 2482 @ 40), (N/A, 20), (N/A)
(5170 - 5250 @ 80), (N/A, 20), (N/A)
(5250 - 5330 @ 80), (N/A, 20), (0 ms), DFS
(5490 - 5710 @ 160), (N/A, 27), (0 ms), DFS
(57000 - 66000 @ 2160), (N/A, 40), (N/A)
问题：
<channel-frequency-range> @ <channel-width>），但我不确定其他列。iw phyoriw list命令的输出应该如何兼容？例如，在我的系统中，我得到如下所示的iw list命令输出（我只考虑了与 5.0 GHz 频段相关的部分）。给定“N / A”的存在对于5170 - 5250频率范围的iw reg get命令，不应该这些频率显示为(disabled)在iw list的输出？区别是基于通道宽度吗？但话说回来，为什么不iw reg get包括 20 MHz 信道宽度的结果？
Band 2:
Capabilities: 0x2fe
HT20/HT40
SM Power Save disabled
RX Greenfield
RX HT20 SGI
RX HT40 SGI
TX STBC
RX STBC 2-streams
Max AMSDU length: 3839 bytes
No DSSS/CCK HT40
Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
Minimum RX AMPDU time spacing: 2 usec (0x04)
HT TX/RX MCS rate indexes supported: 0-15, 32
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] (20.0 dBm)
* 5190 MHz [38] (20.0 dBm)
* 5200 MHz [40] (20.0 dBm)
* 5210 MHz [42] (20.0 dBm)
* 5220 MHz [44] (20.0 dBm)
* 5230 MHz [46] (20.0 dBm)
* 5240 MHz [48] (20.0 dBm)
* 5250 MHz [50] (disabled)
* 5260 MHz [52] (20.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5270 MHz [54] (20.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5280 MHz [56] (20.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5290 MHz [58] (20.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5300 MHz [60] (20.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5310 MHz [62] (20.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5320 MHz [64] (20.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5500 MHz [100] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5510 MHz [102] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5520 MHz [104] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5530 MHz [106] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5540 MHz [108] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5550 MHz [110] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5560 MHz [112] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5570 MHz [114] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5580 MHz [116] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5590 MHz [118] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5600 MHz [120] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5610 MHz [122] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5620 MHz [124] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5630 MHz [126] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5640 MHz [128] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5650 MHz [130] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5660 MHz [132] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5670 MHz [134] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5680 MHz [136] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5690 MHz [138] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5700 MHz [140] (27.0 dBm) (radar detection)
DFS state: usable (for 1693 sec)
DFS CAC time: 60000 ms
* 5745 MHz [149] (disabled)
* 5755 MHz [151] (disabled)
* 5765 MHz [153] (disabled)
* 5775 MHz [155] (disabled)
* 5785 MHz [157] (disabled)
* 5795 MHz [159] (disabled)
* 5805 MHz [161] (disabled)
* 5825 MHz [165] (disabled)
* 4920 MHz [184] (disabled)
* 4940 MHz [188] (disabled)
* 4960 MHz [192] (disabled)
* 4980 MHz [196] (disabled)
有趣的问题，我不知道答案，所以我是这样发现的：
3.17的源代码显示了数据的来源。特别是，
(5250 - 5330 @ 80)是此特定规则适用的频率范围和最大带宽（因此您不需要 40 MHz 带宽和 20 MHz 带宽的两个规则）(N/A, 20)是最大天线增益和最大 EIRP（有效各向同性辐射功率）。(0 ms)是 DFS（动态频率选择）CAC（信道可用性检查）时间。我不知道零值是否特殊。DFS包含各种标志；同样，DFS 是动态频率选择。N/A并不意味着“这应该被禁用”，这意味着“对此没有规定”。有些国家会限制最大天线增益，有些国家会限制最大 EIRP，等等。
因此，实际值不应超过法规限制，但只要符合法规，任何值都可以。