It should be in "Wireless" properties in your wireless router.
The exact method to disable the broadcast of your SSID will vary depending on your router. Most routers have an option directly within the settings which will allow you the option to mask the broadcast of your SSID.
firewall disable
disable an SSID broadcast
SSID
Hiding or changing the broadcast of your SSID is a security measure. An SSID that is not displayed prevents outside users from recognizing your network. It can also prevent any attempts to hijack your network.
Disable SSID broadcasts
An SSID is any name you want to give to your wireless network router (to identify it) up to 32 characters long. Frequestly the SSID has a default that is supplied by the router manufacturer. it is important ,not to broadcast ur ssid ,also change ur ssid name.
It's recommended to turn off ssid broadcast.
Ssid broadcast
Disabling the SSID Broadcast.
Disable the broadcast of the SSID on the access point.
overlapping channel,broadcast SSID