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I said ‘where appropriate’. It’s unlikely to be rolled out fully throughout the entirety of the providers network. So you’ll see it in high density areas where

by opless 6y ago

I said ‘where appropriate’. It’s unlikely to be rolled out fully throughout the entirety of the providers network. So you’ll see it in high density areas where people are mostly outside. As I said, malls etc. Also higher speeds at the regular sub-ghz frequencies are achievable through beam-forming.

totalZero 6y ago
To send more data per second, you either need a carrier wave of higher frequency (which 5G is doing), or an increased number of simultaneous data streams at the present frequency (which 5G is also doing). Beamforming can't overstep the physical limitations of a carrier wave, it just adapts the radiation pattern of the antenna array to improve range and reduce interference. This is useful to extend the range of high-band signals, because they operate in object-dense space with a high density of clients. It is also useful at the lower frequencies, because it allows an improvement in spectrum efficiency in an otherwise crowded part of the spectrum. You are basically saying that beamforming allows more single-user MIMO to improve the data speed of an individual user's connection at the lower frequencies. I agree with that. However, you still need more base stations because (A) you won't see the massive advertised 5G speeds without sub-6GHz and mm-wave, and (B) you need more antennas as you improve MIMO to serve more simultaneous data streams to each individual user at sub-GHz. I am not familiar with the authors of this paper (https://arxiv.org/pdf/1902.07678.pdf https://arxiv.org/pdf/1902.07678.pdf), but it offers a good explanation with some images: The spectral efficiency of Massive MIMO grows monotonically with the number of antennas [28]. Thus, we can expect a future where hundreds or thousands of antennas are used to serve a set of users. There are, however, practical limits to how many antennas can be deployed at conventional towers and rooftop locations, for example, determined by the array dimensions allowed by the site owner, the weight, and the wind load. [...] Nevertheless, the spatial multiplexing capability of these two dimensional planar arrays in our three-dimensional world is far from what has been demonstrated in the academic literature, where large one-dimensional arrays are often considered in a two-dimensional world. In many practical deployment scenarios, the user channels are mainly separable in the horizontal domain [35] since the variations in elevation angle between different users and scattering objects are relatively small. [...] However, to deploy more than a few hundred antennas per site and to obtain a truly massive spatial resolution in the horizontal domain, we need new antenna deployment strategies. Instead of gathering all the antennas in a single box, which will be visible and heavy, the antennas can be distributed over a substantially larger area and made invisible by integrating them into existing construction elements. Also, you're going to see mid-band (sub-6GHz) rolled out in a lot of places where mm-wave wouldn't be appropriate.
- opless 6y ago
  ... as I said ‘where appropriate’. However I don’t think for one minute that you’re going to get that super fast data everywhere. :-)

by opless 6y ago

totalZero 6y ago

To send more data per second, you either need a carrier wave of higher frequency (which 5G is doing), or an increased number of simultaneous data streams at the present frequency (which 5G is also doing). Beamforming can't overstep the physical limitations of a carrier wave, it just adapts the radiation pattern of the antenna array to improve range and reduce interference. This is useful to extend the range of high-band signals, because they operate in object-dense space with a high density of clients. It is also useful at the lower frequencies, because it allows an improvement in spectrum efficiency in an otherwise crowded part of the spectrum. You are basically saying that beamforming allows more single-user MIMO to improve the data speed of an individual user's connection at the lower frequencies. I agree with that. However, you still need more base stations because (A) you won't see the massive advertised 5G speeds without sub-6GHz and mm-wave, and (B) you need more antennas as you improve MIMO to serve more simultaneous data streams to each individual user at sub-GHz. I am not familiar with the authors of this paper (https://arxiv.org/pdf/1902.07678.pdf https://arxiv.org/pdf/1902.07678.pdf), but it offers a good explanation with some images: The spectral efficiency of Massive MIMO grows monotonically with the number of antennas [28]. Thus, we can expect a future where hundreds or thousands of antennas are used to serve a set of users. There are, however, practical limits to how many antennas can be deployed at conventional towers and rooftop locations, for example, determined by the array dimensions allowed by the site owner, the weight, and the wind load. [...] Nevertheless, the spatial multiplexing capability of these two dimensional planar arrays in our three-dimensional world is far from what has been demonstrated in the academic literature, where large one-dimensional arrays are often considered in a two-dimensional world. In many practical deployment scenarios, the user channels are mainly separable in the horizontal domain [35] since the variations in elevation angle between different users and scattering objects are relatively small. [...] However, to deploy more than a few hundred antennas per site and to obtain a truly massive spatial resolution in the horizontal domain, we need new antenna deployment strategies. Instead of gathering all the antennas in a single box, which will be visible and heavy, the antennas can be distributed over a substantially larger area and made invisible by integrating them into existing construction elements. Also, you're going to see mid-band (sub-6GHz) rolled out in a lot of places where mm-wave wouldn't be appropriate.

opless 6y ago
... as I said ‘where appropriate’. However I don’t think for one minute that you’re going to get that super fast data everywhere. :-)