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10

First of all, you're doing something VERY right that a lot of IoT designers and users don't: You consider the fact that operation needs to be reliable and latency-bounded. Not everyone does that, and that's why many IoT devices really are bad. The choice of standard between 802.11 b/g/n won't really influence your latency much. I assume we're bounding ...


10

Regardless of which chip is which, it is unlikely that there is an ethernet connection in there anywhere. The processor talks to the wifi module directly rather than over ethernet. Sony wouldn't include the ethernet chips and transformers if there's no external ethernet connection If you need a wired ethernet connection, you will have to get yourself a ...


8

You cannot really infer 54 Mbps knowing only the bandwidth. It's a design tradeoff. You could theoretically build a system that would do twice this throughput in the same bandwidth under ideal conditions. The trade-off involves multiple factors, such as power requirements, implementation complexity, robustness in the face of various types of interference, ...


6

802.11 specifies operation in the 2.4 GHz band. This is one of the industrial, scientific and medical (ISM) radio bands, which are used for quite a lot more than Wi-Fi. The ISM bands were in fact allocated for non-telecommunications use, where devices that must necessarily spew RF interference may do so. In the US Wi-Fi gets to operate here under FCC part 15 ...


5

Unless you are talking astronomical volumes, it's just not going to happen in your price range with parts that are currently on the market. The cheapest wifi implementations tend to be no-name USB dongles (about at your total price point), but to use one of those you need to have a microcontroller with USB host capability, which all by itself exceeds your ...


4

Bluetooth is IEEE 802.15.1. Bluetooth does not implement 802.11. However, it is not completely correct that Bluetooth "does nothing" with 802.11. Bluetooth v3.0 + HS allows for the alternate MAC/PHY (AMP) feature. The basic idea is that devices can use Bluetooth for coordination and small data transmissions, switching to 802.11 in a controlled way to ...


4

Short answer: you combine it with a backend :-) The MAX2831 you mention is a transceiver and that is all it does. As the manufacturer says, its a "frontend". What you miss is the "backend". Guess which part is even more complicated ? ;-) The frontend contains only the radios needed to send (TX) and receive (RX) ! It does NOT generate the WiFi signal, I ...


3

Sure, just attenuate it (50-60dB). You don't want to saturate the receiver. As for collisions, they happen on air too (at different power levels). If you have a MIMO NIC with multiple SMAs, you can even play with the phase a bit.


3

27Mbps each? You wish! For starters, bear in mind that routers don't simply "stream" data like a TV transmitter, they just provide a path for other devices to carry out two way communication using higher levels of protocol such as FTP or HTTP that are in turn layered on top of TCP or UDP on top of the wireless frames. That all requires various levels of ...


3

Channel usage information is provided by the AP to the non-AP STA to recommend channels for noninfrastructure networks or an off-channel TDLS direct link. The non-AP STAs can use the channel usage information as part of channel selection processing for a noninfrastructure network or an off-channel TDLS direct link. At page 58. The AP Channel Report ...


2

If your equipment supports it, you can set it to Channel 155, however, this is not desirable, as you will get interference from the two adjacent channels. The recommendations are just that, recommendations. There are no requirements in FCC 15.245 or 15.247 (ISM regulations) for a specific channel, as long as you are not near the band's edge. Edit: ...


2

Modulation and Coding Scheme (MCS) indices determine the data rate in 802.11, based on the SNR observed. Each index uses a pre-defined modulation scheme (upto 256-QAM in VHT modes) and a coding rate (upto 5/6), which in turn influences the data rate. Note that higher your data rate, higher would be the SNR requirement. This should give you a neat idea.


2

As usual, it depends. Let's restrict ourselves to the OFDM-based IEEE802.11 standards (a,g,n,ac,p, and many more). These have a typical frame structure, in which one symbol, which is always BPSK-modulated, contains the rate setting info (and thus, implicitly, the modulation used). As an example: Got this graphic from keysight See the violet symbol. ...


2

Communication standards usually, and especially 802.11, do not specify antennas. So, there's no "standard antennas". Which antenna you use depends on your use case; and in the case of WiFi and similar technologies, using highly directive antennas makes no sense, since you can't know in which direction your communication partner is, seeing that usually at ...


1

The problem you have with single symbol transmission is clock synchronization. This is a problem for any transmission standard. In a slow AM, FM or QAM transmission you might get away with slightly desynchronized clocks as long as you sample at any point where the symbol is valid on the receiver side (which is basically the symbol time minus the transition ...


1

Assuming "what is the full form?" means "what does the acronym stand for?"... Project Authorization Request (PAR) https://standards.ieee.org/develop/par.html


1

There are pro's and cons of predictable and unpredictable noise models. Each can respectively give an estimate of packet loss with tolerances or a probability curve. But there are always exceptions from Doppler velocity and Rician Fading due to reflections or NLoS paths. A sensor-based Doppler-shift prediction and compensation approach outperforms a ...


1

As pointed out by Marcus in the previous answer, the IEEE standards do not prescribe a type of antenna that has to be employed. Based on the functionality, one would pick an appropriate antenna. For instance, standards 802.11a/b/g do not employ MIMO, and function through the simple use of an omnidirectional antenna that radiates energy in all directions (...


1

Your router will be able to achieve 300 Mbps using 2x2 MIMO coupled with channel bandwidth of 40 MHz (ie. by using two streams each occupying same 40 MHz of channel bandwidth). 802.11g gives peak speed of 54 Mbps with 20 Mhz of Bandwidth. In advancement to 802.11n, speed is improved to 72.2 Mbps (with single stream, 20 MHz channel Bandwidth) by improvement ...


1

Multiple antennas on routers are used for beam-forming. Each antenna can handle whatever standards the router supports, but the more antennas the router has the better job it can do to form directional capability to reach each device that is connected. I suggest you do some searches on Amazon and Google and read the specs for different routers that have ...


1

1) Because the symbol-recognition algorithms would differ across the subcarriers. 2) Because the phase noise tolerance would differ across the subcarriers, affecting how precisely the packet-packet phase-delta must be controlled.


1

If you view the cable as a transmission line, you can model all of its characteristics using standard transmission line formulas. This suggests that single frequency tests at the spectrum limits should provide most of the needed information. Take care however, that your tests also examine group delays given the wide spectrum of the application. With careful ...


1

The premise that a higher raw data rate implies a higher packet rate is false. The packet rate would only go up if the network were already saturated with traffic, and the application actually transmitted more packets as a result of the increased available bandwidth. All other parameters being equal (packet size, payload bandwidth, etc.) a higher raw data ...


1

WiFi antennas are naturally omni-directional and this means that they produce an even EM coverage to potential users in their localized area. An omni-directional field pattern means they cannot target "direction" like a radar does. On the other hand, if they used antenna diversity they could take a stab at it. As regards distance (range), the amplitude of ...


1

Well, "I'm thinking of building a signal beacon designed to be used indoors." Indoor can be an 3 bedroom apartment or an entire factory or a huge parking lot. Majority of the Bluetooth Low Energy module manufacturers claim to have achieved a 100 m line-of-sight range with On-chip (No external) antenna. I have evaluated 3 different BLE modules from one the ...


1

No, you can't use a Zigbee specific processor in a 802.11 WLAN. They're not reprogrammable. You might want to take a look at the ESP8266, which is a (slow) Wifi module that seems to be reprogrammable. Adafruit Link to a Module https://www.adafruit.com/products/2282 Instructables Link to a How-To http://www.instructables.com/id/Getting-Started-with-the-...


1

No. Bluetooth standard is 802.15 although it doesn't do anything with the 802.11 standard of operation. Bluetooth and WiFi (802.11) both share the 2.4GHz band, which causes some interference if not implemented properly. This is why Bluetooth uses FHSS (Frequency Hopping Spread Spectrum) and also why you'll see some Bluetooth devices say they operate ...


1

Historical reasons. The original channel allocation is for 802.11 and 802.11b, which has 11 non-overlapping channels. The 802.11g standard increases the bandwidth used, which means that channel 1 is really spanning channels -1..3, channel 6 is really spanning channels 4..8, and channel 11 is really spanning channels 9..13, which is the only configuration ...


1

The same antenna can be and is used for both TX and RX. However, in MIMO, SIMO and MOSI systems, you can have multiple RX antennas for the same TX, multiple TX to RX antennas and basically any number of combinations. Usually in MIMO it's for example 3x3 (3TX and 3RX).


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