同的国家和地区规定了在本国或本地区可以使用的信道、射频信号在信道中的最大发射功率。工作在不同信道的射频信号，信号强度可能会有差别。国家码和信道顺从表、各信道的功率限制值、信道编号和频率。
开发人员需要一份国家对应得信道列表，用于限制用户的配置。原厂sdk的驱动中有对应的列表，但一般比较庞大难懂，提取出来也很麻烦。如果设备支持AC控制，AC的配置页面也需要该列表，解决方法是给一个通用接口提供页面查询。在开发过程中，也经常遇到国家代码问题，所以就花时间将国家码顺从表整理成了数据库、json、数组，开发者可以根据个人喜好来调用。
考虑到该顺从表非常庞大，将信道列表按位存储，这样可以节省很多空间，如果直接存在c代码中，通过编译，占用的空间就更小了。当然，如果是在AC端直接可以用数据库方式查询，所以数据库设计也没有考虑空间问题，一共才3000多条记录，占几十K，可以忽略。也可以生成json配置文件，这种做法跟数据库差不多，但考虑到json文件太大，就没有去生成了。
// 无线模式列表
char *CCODE_RADIO_MODE_LIST[] = {
"11b", // 0
"11bg", // 1
"11g",
"11gnonly",
"11gn",
"11gnonly40+",
"11gn40+",
"11gnonly40-",
"11gn40-",
"11a",
"11anonly", // 10
"11an",
"11anonly40+",
"11an40+",
"11anonly40-",
"11an40-",
"11acvht", // 16
"11acvht40+",
"11acvht40-",
"11acvht80"
};
// 可用信道列表
int CHANNEL_TABLE_24G[] = {1,2,3,4,5,6,7,8,9,10,11,12,13,14};
int CHANNEL_TABLE_5G[] = {36,40,44,48,52,56,60,64,100,104,108,112,116,120,124,128,132,136,140,149,153,157,161,165,169,173};
// 结构体
typedef struct country_node{
u_int8_t radio_type;
char cname[3];
u_int8_t wl_mode;
u_int8_t min_tx;
u_int8_t max_tx;
u_int32_t channel_bits;
}country_node_t;
// 信道顺从表
country_node_t country_table[] =
{
{0,"HN",0,3,27,0x1fff},
{0,"HN",1,3,27,0x1fff},
{0,"HN",2,3,27,0x1fff},
{0,"HN",3,3,27,0x1fff},
{0,"HN",4,3,27,0x1fff},
{0,"HN",5,3,27,0x1ff},
{0,"HN",6,3,27,0x1ff},
{0,"HN",7,3,27,0x1ff0},
{0,"HN",8,3,27,0x1ff0},
{0,"MC",0,3,27,0x1fff},
{0,"MC",1,3,27,0x1fff},
{0,"MC",2,3,27,0x1fff},
{0,"MC",3,3,27,0x1fff},
{0,"MC",4,3,27,0x1fff},
{0,"MC",5,3,27,0x1ff},
{0,"MC",6,3,27,0x1ff},
{0,"MC",7,3,27,0x1ff0},
{0,"MC",8,3,27,0x1ff0},
{0,"PE",0,3,27,0x1fff},
{0,"PE",1,3,27,0x1fff},
{0,"PE",2,3,27,0x1fff},
{0,"PE",3,3,27,0x1fff},
{0,"PE",4,3,27,0x1fff},
{0,"PE",5,3,27,0x1ff},
{0,"PE",6,3,27,0x1ff},
{0,"PE",7,3,27,0x1ff0},
{0,"PE",8,3,27,0x1ff0},
{0,"MU",0,3,27,0x1fff},
{0,"MU",1,3,27,0x1fff},
{0,"MU",2,3,27,0x1fff},
{0,"MU",3,3,27,0x1fff},
{0,"MU",4,3,27,0x1fff},
{0,"MU",5,3,27,0x1ff},
{0,"MU",6,3,27,0x1ff},
{0,"MU",7,3,27,0x1ff0},
{0,"MU",8,3,27,0x1ff0},
{0,"CI",0,3,27,0x1fff},
{0,"CI",1,3,27,0x1fff},
{0,"CI",2,3,27,0x1fff},
{0,"CI",3,3,27,0x1fff},
{0,"CI",4,3,27,0x1fff},
{0,"CI",5,3,27,0x1ff},
{0,"CI",6,3,27,0x1ff},
{0,"CI",7,3,27,0x1ff0},
{0,"CI",8,3,27,0x1ff0},
{0,"PA",0,3,27,0x7ff},
{0,"PA",1,3,27,0x7ff},
{0,"PA",2,3,27,0x7ff},
{0,"PA",3,3,27,0x7ff},
{0,"PA",4,3,27,0x7ff},
{0,"PA",5,3,27,0x7f},
{0,"PA",6,3,27,0x7f},
{0,"PA",7,3,27,0x7f0},
{0,"PA",8,3,27,0x7f0},
{0,"PK",0,3,27,0x1fff},
{0,"PK",1,3,27,0x1fff},
{0,"PK",2,3,27,0x1fff},
{0,"PK",3,3,27,0x1fff},
{0,"PK",4,3,27,0x1fff},
{0,"PK",5,3,27,0x1ff},
{0,"PK",6,3,27,0x1ff},
{0,"PK",7,3,27,0x1ff0},
{0,"PK",8,3,27,0x1ff0},
{0,"WS",0,3,27,0x1fff},
{0,"WS",1,3,27,0x1fff},
{0,"WS",2,3,27,0x1fff},
{0,"WS",3,3,27,0x1fff},
{0,"WS",4,3,27,0x1fff},
{0,"WS",5,3,27,0x1ff},
{0,"WS",6,3,27,0x1ff},
{0,"WS",7,3,27,0x1ff0},
{0,"WS",8,3,27,0x1ff0},
{0,"CO",0,3,27,0x1fff},
{0,"CO",1,3,27,0x1fff},
{0,"CO",2,3,27,0x1fff},
{0,"CO",3,3,27,0x1fff},
{0,"CO",4,3,27,0x1fff},
{0,"CO",5,3,27,0x1ff},
{0,"CO",6,3,27,0x1ff},
{0,"CO",7,3,27,0x1ff0},
{0,"CO",8,3,27,0x1ff0},
{0,"IL",0,3,27,0x1fff},
{0,"IL",1,3,27,0x1fff},
{0,"IL",2,3,27,0x1fff},
{0,"IL",3,3,27,0x1fff},
{0,"IL",4,3,27,0x1fff},
{0,"IL",5,3,27,0x1ff},
{0,"IL",6,3,27,0x1ff},
{0,"IL",7,3,27,0x1ff0},
{0,"IL",8,3,27,0x1ff0},
{0,"LC",0,3,27,0x1fff},
{0,"LC",1,3,27,0x1fff},
{0,"LC",2,3,27,0x1fff},
{0,"LC",3,3,27,0x1fff},
{0,"LC",4,3,27,0x1fff},
{0,"LC",5,3,27,0x1ff},
{0,"LC",6,3,27,0x1ff},
{0,"LC",7,3,27,0x1ff0},
{0,"LC",8,3,27,0x1ff0},
{0,"HK",0,3,27,0x1fff},
{0,"HK",1,3,27,0x1fff},
{0,"HK",2,3,27,0x1fff},
{0,"HK",3,3,27,0x1fff},
{0,"HK",4,3,27,0x1fff},
{0,"HK",5,3,27,0x1ff},
{0,"HK",6,3,27,0x1ff},
{0,"HK",7,3,27,0x1ff0},
{0,"HK",8,3,27,0x1ff0},
{0,"BR",0,3,27,0x1fff},
{0,"BR",1,3,27,0x1fff},
{0,"BR",2,3,27,0x1fff},
{0,"BR",3,3,27,0x1fff},
{0,"BR",4,3,27,0x1fff},
{0,"BR",5,3,27,0x1ff},
{0,"BR",6,3,27,0x1ff},
{0,"BR",7,3,27,0x1ff0},
{0,"BR",8,3,27,0x1ff0},
{0,"DZ",0,3,27,0x1fff},
{0,"DZ",1,3,27,0x1fff},
{0,"DZ",2,3,27,0x1fff},
{0,"DZ",3,3,27,0x1fff},
{0,"DZ",4,3,27,0x1fff},
{0,"DZ",5,3,27,0x1ff},
{0,"DZ",6,3,27,0x1ff},
{0,"DZ",7,3,27,0x1ff0},
{0,"DZ",8,3,27,0x1ff0},
{0,"RO",0,3,27,0x1fff},
{0,"RO",1,3,27,0x1fff},
{0,"RO",2,3,27,0x1fff},
{0,"RO",3,3,27,0x1fff},
{0,"RO",4,3,27,0x1fff},
{0,"RO",5,3,27,0x1ff},
{0,"RO",6,3,27,0x1ff},
{0,"RO",7,3,27,0x1ff0},
{0,"RO",8,3,27,0x1ff0},
{0,"GT",0,3,27,0x1fff},
{0,"GT",1,3,27,0x1fff},
{0,"GT",2,3,27,0x1fff},
{0,"GT",3,3,27,0x1fff},
{0,"GT",4,3,27,0x1fff},
{0,"GT",5,3,27,0x1ff},
// 由于表较大，没全部放在这里了，需要的自行下载，下载地址见下文- 位设计
CHANNEL_TABLE_24G表示2.4G所有支持信道
CHANNEL_TABLE_5G表示5G所有支持信道
如2.4G,如果channel_bits为0x1fff，信道列表位1,2,3,4,5,6,7,8,9,10,11,12,13-数据库字段说明
编号 国家代码 radio_type(0表示2.4g,1表示5g) 无线模式 最小支持功率 最大支持功率 可用信道列表（含该信道支持功率）
3221|768|1|11anonly40+|5|27|36-5-20,44-5-20,52-5-20,60-5-20,100-5-27,108-5-27,116-5-27,124-5-27,132-5-27
3222|768|1|11an40+|5|27|36-5-20,44-5-20,52-5-20,60-5-20,100-5-27,108-5-27,116-5-27,124-5-27,132-5-27
3223|768|1|11anonly40-|5|27|40-5-20,48-5-20,56-5-20,64-5-20,104-5-27,112-5-27,120-5-27,128-5-27,136-5-27
3224|768|1|11an40-|5|27|40-5-20,48-5-20,56-5-20,64-5-20,104-5-27,112-5-27,120-5-27,128-5-27,136-5-27-数据库查询范例
1. 查询国家码为156，radio为5G的列表：
2. 查询国家码为US(840)，radio为5G,无线模式为11acvht40+的可用信道列表
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