There are ‘heat map’ style apps on your phone you can use to plot coverage across your premises.
Try those with your antennas in various positions and orientation and see what is best.
Having too much 2.4Ghz signal (WiFi, ZigBee, BlueTooth all share similar frequencies) in close proximity is also going to cause grief and interference. Try and space them out a bit if possible. If using more recent 5Ghz and 6Ghz bands to try and get around this, make sure you are not confusing devices that can only use the 2.4Ghz band exclusively. If setting up sub-lans to separate IOT networks from everything else, make sure that some essential things like timekeeping NTP, and IPv6 for Matter are still catered for. Don’t lock it up too tight without considering the implications.
Think like the radio signals do - what is the closest path with least interference I can safely and reliably travel to get to my final destination, and back again?
Yes, most protocols have error correction and retransmission functionality, but you should strive to keep those to a minimum rather than rely on them always.
Upping your device radio transmission transmit levels can often backfire, as the surrounding receivers are now swamped. You cannot control what your neighbours do, but be responsible yourself. If you suspect any such interference, a temporary shield of aluminiuum cooking foil between them and you can be used to check if it makes much difference. If it does, put it on the back of a picture hanging on the wall can be most effective. Make sure the ground wire is well hidden in case kids find it and pull on it. Correspondingly, there is metallic wallpaper that can completely shield a whole room, turning it into a Faraday Cage. Same with foil insulation, usually found in roofs and outside walls, where signal reflections can play havoc with carefully planned antenna pointing exercises, but protect you from the neighbour across the street that has their brand new gamer router WiFi radios turned up to maximum boost with added antennas, so his Playstation can get the best ping and latency times. Smirks: there are ways to remedy this, not all legal, and a knock on the door to offer useful advice can beat a carefully focused wideband noise interference generator any time! Window and door glass tinting is often metallic and has reflective as well as shielding properties.
Channel selection should be left on automatic unless you have control over all channels that can be seen. Again, there are tools you can use to examine which channels are less used or free. Some devices are smart and constantly look for the best, while others only check at power on time.
Antenna orientation can make a difference. Move the device in 3 dimensions to see which picks up the best signal. Putting a distant device in the focal point of a parabolic reflector can sometimes work wonders to punch a line of sight signal through.
Be patient if you have mesh devices that need time to heal and discover best paths. Correspondingly, once they are stable, do not disrupt them by uncalled for resets.
While wireless is convenient, it is also a major source of grief if it is marginal and intermittent. Hard wiring, shielded from interference, is far better. Consider cat 6 or above twisted pair wiring to connect distant access points together. Ethernet, RS485, fiber optics, whatever, as long as the data gets through, reliably and consistently. In a multi-storey building, consider a floor to floor hard-wired backbone, with wireless access separated by floor, and all going back to a central switch and router. Shortest path is best, but other considerations including WAF, technology creep, and cost often override this.
If you are considering adding a facilities cabinet to bring everything together, don’t forget adequate ventilation and a reliable power source. Keep dust and heat out. Adding a small UPS to keep critical networking components working during short power interruptions should be part of your scope of works. Bonus is most UPSs contain power filters to improve longevity and reliability of connected devices. Don’t put everything inside a metal cabinet and wonder where all the signals went - see ‘Faraday Cage’. Physical access security is also essential to prevent unwanted theft, reconfiguration or interference.
Carefully bundling all your wiring together for neatness and tying it up with cable ties might look good, but unless they are twisted pair and shielded, you may be introducing cross coupling, hum, and interference. Keep data and power cabling seperate if possible, and if they cross, keep it at right angles to minimise crosstalk.
Cheapest is not always best. Design and planning will always trump reactive troubleshooting. Try to eliminate luck from the equation.
, if you on the other hand mean “least resistance” in terms of Signals “desire” to free “Circumstances”, i would say … Don’t buy anymore IOT, find another Hobby
