While I have separated out satellite and 3g/4g from the wireless section, I am going to include both WiFi and microwave here.
WiFi is ultimately not a good technology to use when webcasting anything other than low-bandwidth video or audio-only content. WiFi is prone to great variability in signal strength. A typical setup is to test with WiFi in an empty venue. Then, although everything seemed fine, when 200 delegates arrive at the conference, two things happen. First, they all connect to the WiFi themselves, causing both a contention issue and a radio spectrum issue - literally competing with your webcast for the radio capacity. The second drawback is that human beings are largely water, and water is highly absorbent of radio signals - so by the time the venue is full, your WiFi signal is weak and unreliable. That is not to say that WiFi can’t be used - and in many cases it may be the only way to get breaking news out - so it is important to practice and test webcasting over WiFi as you learn the general webcast skills. But, if there is another option, then almost invariably that option is better for contribution feeds. Moreover it is important to keep in mind that the WiFi router itself is likely connected to a wired line out of the building - so it is important to have a full understanding of that line and its capacity to support your feed.
While also a radio technology, microwave tends to refer to directional point to point links. A typical microwave link is similar in many ways to a WiFi link in that one end will be connected to a wired line. However, the directional capability means that microwave links can be established over long distances, which can be 50 m to 2 km, and if well set up, they can be very reliable. Microwaves are typically uncontended, so in some ways they are thought of as extending the fixed line to a remote location.
The logistics of finding a fixed line, and establishing a remote microwave link, may be complex, so this should be set up well in advance of an event. There are additionally some problems that are particular to microwave links: one of my favorite stories is what we experienced covering some political commentary in a street in London. Every now and then the signal would fail, and we would scramble around trying to work out why the link had dropped. Everything technically seemed fine, apart from the fact that we would, approximately every 10 minutes, have a 2 minute outage.
It was only when we stood outside our production vehicle for a full cycle that we realized that the number 22 bus was stopping directly between our microwave terminal and the remote location, simply blocking the line of sight between the two points! We fixed the issue by raising the link up to a first floor balcony and dropping the cables down to the production truck, but it was quite embarrassing having to explain to the client that a bus had caused the outages.