# Tag Info

11

The ESP8266 chip is relatively new to the market (circa 2014, I think). So it's short market availability has limited its adoption somewhat -- some early adopters have chosen it, but that's usually not a benefit to high volume, low cost designs. There are also many more well tested chips/modules that have better documentation and better support. TI, Silicon ...

8

Energy moves through the cable in both directions simultaneously. Just as different video signals are modulated on different channel frequencies, incoming and outgoing data streams are modulated on different carrier frequencies, and pass each other without interference.

5

GSM by itself does not support data, just voice (even SMS is put ontop of GSM). Data service, beyond the 9600baud CSD (which doesn't seem to be supported by most phones/mobile providers anymore) requires the availability of GPRS or EDGE. Although both systems are very old, depending on where you are, there are still base stations around that only support GSM ...

4

It’s limited by the same criteria as any medium: Shannon’s information theorem. Basically, bandwidth * SNR. More precisely, the Shannon-Hartley Equation: $C = B \; log_2 \left( 1 + \frac{S}{N}\right) \;\;\;\;\;\;\;\;\;\; \rightarrow (1)$ Where $B$ is bandwidth in Hz, $\frac{S}{N}$ is the signal-to-noise ratio. As a practical example, under the ...

4

You've obviously been looking in the wrong places. All non-standalone Wifi chipsets (like, the one in your smartphone or laptop or router) only do the physical modulation, demodulation, and a bit of the data link layer (namely, medium access control (MAC), simply because you must do that in hardware that's very close to the physical layer and low-latency). ...

4

This is the kind of thing that I do all day long. One area for you to examine is called fiber optic thermometry (or phosphor thermometry or fluoroptic thermometry.) Some fibers can be built to withstand as much as $450\:^\circ\textrm{C}$, and more if you have enough money. They are very resistant to chemical attack, as well, and can be built to use very ...

3

If I were you, I would use MQTT messaging protocol. It is simple and easy to use. But it requires a broker (server) machine to work. I recommend reading this article about MQTT. Also it is really easy to add more sensor to the system. Your system should be like this if you use MQTT: Device #1, #2: "publishers", they are in deep-sleep for the most of the ...

3

To answer your specific question, 'is there a better alternative for mass production', of course there is. That alternative is the same for any module, nothing I am about to say is specific to the ESP8266. The better alternative to using the ESP8266 module in the context of mass production is using the ESP8266 chip. The modules have the advantage of ...

2

Internet over CATV is called DOCSIS (https://en.wikipedia.org/wiki/DOCSIS). It uses several channels separated by frequency for downstream and upstream. Think about FM radio. How can you have several channels on radio? They just use different frequencies. This is called "Frequency-division multiplexing" (https://en.wikipedia.org/wiki/Frequency-...

2

That isn't a module, it's the actual chip. I doubt that you would be able to purchase chips in small quantities at all. Instead, you'll have to work with the third-party modules listed near the bottom of that page. Even those are very small, and you'll have to learn how to do surface-mount assembly.

2

Yes, wireless Internet is a thing, it's called WiFi. And satellite-based Internet is a thing, too. There are many providers of such services. But keep in mind that Internet in general requires two-way communication. It is not a broadcast service like radio and TV. Even watching or listening to streaming audio and video services requires two-way communication....

2

There isn't much information in your question, but I'll explain one common way you can solve this type of problem. In short: You need to get more troubleshooting data, and then use your critical thinking skills to find the cause of the problem by using that data. Remember that responses like "HTTP 400 Bad Request" come from the HTTP server. Therefore you ...

1

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My advice for you for moving from a POC to a real product is: Doing a lot of testing. Think of everything that could go wrong and setup some good test cases, also at different temperatures.

1

You may have that peak bandwidth available on your particular phone. LTE is very adaptive. When you want a burst of data, you get a burst of data. When you don't, others are using those spectrum resources. This is an excellent overview of how the system works.

1

If upstream of the wiring that leads to the AC power socket there is equipment that adds noise to that upstream feed line then, that noise (as a voltage fluctuation) will also be seen down stream at the unused AC power socket. That can capacitively couple to the CAT-5 cable (or any cable within reason) and it could cause cross-interference problems. Having ...

1

Since product recommendation questions are off-topic, I'll answer the underlying question of How small could a fully functional 2G/3G/4G module possibly become? The answer to that lies in physics: The wavelengths involved in these microwave cellular standards are in the range of 10 to 30 cm. Efficient antennas are typically in the order of ¼ of the ...

1

Radio frequency communications operate the same when travelling through a coaxial cable as they do through open-air. They are just shielded from outside interference (called ingress) and leakage (called egress). As such, signals of differing frequencies can co-exist, with each travelling in different directions. Amplification, however, is a different story. ...

1

If you can't keep track of which cable is which by labelling them, then you'll have to do the testing in any case. At which point, you might as well connect them physically in the right order, and avoid the expense and other penalties associated with an electronic sorting mechanism.

1

After reading a short tutorial on the ESP8266 module using the Arduino API, I found that replacing the "GET" string with a "PUT" string with the command following. Specifically, to send the command {"on": true} to the resource at /state The ESP8266 would execute: String command = "{\"on\": true}"; client.print(String("PUT ") + "/state" + "HTTP/1.1 \r\n" ...

1

Long time ago, I worked at a company which developed silicon for receivers of internet transmitted from TV stations. One day after explaining the idea to a friend, I've got the following response: "So, is the ISP going to broadcast eBay?" A TV station can broadcast 20 high quality signals, they reach tens of thousands (rural) subscribers, each subscriber ...

1

Actually, there have been several efforts in industry and government to work towards systems like this. However, there have not been any mass deployments to date. The IEEE standards include 802.11af and 802.22. The process for making unlicensed spectrum available is under study by the FCC in the United States. See https://en.wikipedia.org/wiki/Super_Wi-...

1

Sending streaming video tends to use some resources. I have streamed video on an intel galileo and that used about 0.5 amps. There is a way to stream without using an OS, but integrating that into your digital system wouldn't be very cohesive. I have one of these wireless video for my backup camera eBay backup cam, but the range is not very good. I think ...

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