& cplSiteName &

NLoS Backhaul Needed for Small Cells

Heavy Lifting Analyst Notes
Heavy Lifting Analyst Notes
Heavy Lifting Analyst Notes
10/16/2013

Over the past few months, Heavy Reading has been investigating the major challenges mobile operators face in deploying outdoor small cells as a capacity layer to handle data traffic growth in urban settings. Operators such as Softbank have the advantage of leveraging existing fiber links to backhaul small-cell traffic to pooled baseband units in telco central offices in Tokyo's densely populated Ginza district. This "cloud RAN" architecture yields blazing fast download speeds, low latency, high quality, and performance even at the cell edge.

But most operators cannot deploy fiber to backhaul small-cell traffic, especially in the dense core of most U.S. cities. Even with aggregation points at hubs on tall buildings or towers, these carriers will need to establish multiple high-capacity, non-line-of-sight (NLoS) links to pole-mounted or street-level small cells over long distances that are frequently blocked by other buildings or trees. Small-cell backhaul links are often blocked by multiple buildings located about 1 km apart, yet they must deliver full capacity. We expect these same requirements to emerge in European cities, as well.

As major mobile carriers start deploying outdoor small cells in urban settings, they will require a "universal wireless transport" solution for backhaul that combines the following attributes:

  • "True NLoS": Instances where a wireless link is completely blocked by multiple solid structures, yet maintains the same dedicated high capacity as a line-of-sight (LoS) link at distances ranging from hundreds of meters to 1 km.

  • Frequency Reuse: The ability to support multiple simultaneous wireless links at full capacity using a single carrier frequency from a common hub location within an overlapping geographical service area. This feature is critical to enable carriers to maximize the use of limited spectral resources within a service area, as well as to minimize capital investments needed to achieve the desired capacity.

This would provide a single toolkit to satisfy a wide range of small-cell backhaul requirements. The combination of NLoS backhaul capacity and range seems critical for cost-effective deployment of the next generation of outdoor small-cell LTE wireless infrastructure for maximum location flexibility. Heavy Reading will be looking for these attributes going forward, as we evaluate NLoS backhaul solutions from the perspective of operators deploying outdoor small cells in urban settings.

Heavy Reading

(4)  | 
Comment  | 
Print  | 
Newest First  |  Oldest First  |  Threaded View        ADD A COMMENT
AmirB52
AmirB52
10/17/2013 | 4:26:55 PM
Re: NLoS is not a telco-grade solution - Operator view
Multiple users on the same site interfere each other. It is well know that when a sector of cellular site serves fewer users the speeds each one of them gets are higher. This is one of the drives for small cells deployments: the users at a given area will spread to multiple small cells instead of being served by one macro cell. I saw it in our network: when a cell is serving close to max possible concurrent users the total backhaul load the cell introduces to the network is lower than when it serve only 5-6 concurrent users ...
HumairRaza
HumairRaza
10/17/2013 | 1:33:58 PM
Re: NLoS is not a telco-grade solution - Operator view
AmirB52

Even if there are multiple users in a cell the capacity still stays the same. You do not need to double or tripple backhaul bandwidth just because there are multiple users in the same cell.
AmirB52
AmirB52
10/16/2013 | 4:45:38 PM
NLoS is not a telco-grade solution - Operator view
We are also investigating solutions for small cell backhaul at our network. As a transmission guys, we went to use our wireless planning tools as we often do with PTP LoS links. But unlike LoS links were planning leads to accurate results of capacity and availability that are easily being deployed, the NLoS gear has no real planning tools, the capacity is something theoretical that stays in the marketing presentations and you get those capacities only 5-10% of the year and only at very short ranges were the installations scernario is more like LoS and sure not NLoS. So NLoS is limited technology that will be deployed only at the places were all other options are not possible.

I saw the "Verizon Deployin Fatter 4G Pipes in NYC" article about Verizon 2x20MHz service with user DL speeds of >80mbps.  Bear in mind that in order to deliver this speed to single user, you need to backhaul ~110mbps , and this is only single user for single site. So I assume Verizon brought at least 300mbps to each small cell in order to deliver peaks of those speeds (because it is not likely to have sole user on the cell site).

 
AmirB52
AmirB52
10/16/2013 | 4:44:54 PM
NLoS is not a telco-grade solution - Operator view
We are also investigating solutions for small cell backhaul at our network. As a transmission guys, we went to use our wireless planning tools as we often do with PTP LoS links. But unlike LoS links were planning leads to accurate results of capacity and availability that are easily being deployed, the NLoS gear has no real planning tools, the capacity is something theoretical that stays in the marketing presentations and you get those capacities only 5-10% of the year and only at very short ranges were the installations scernario is more like LoS and sure not NLoS. So NLoS is limited technology that will be deployed only at the places were all other options are not possible.

I saw the "Verizon Deployin Fatter 4G Pipes in NYC" article about Verizon 2x20MHz service with user DL speeds of >80mbps.  Bear in mind that in order to deliver this speed to single user, you need to backhaul ~110mbps , and this is only single user for single site. So I assume Verizon brought at least 300mbps to each small cell in order to deliver peaks of those speeds (because it is not likely to have sole user on the cell site).

 
Educational Resources
sponsor supplied content
Educational Resources Archive
More Blogs from Heavy Lifting Analyst Notes
A new set of NFV challenges is emerging as operators plan the shift towards cloud-native applications and a container-based strategy.
It's not just about mobile, you know...
Fixed broadband service provider developed its own OSS and BSS systems, a move that gives it cost efficiencies compared with traditional systems and advanced data analysis capabilities, according to its executives.
Among the many considerations facing network operators as they make the leap into the 5G world, service assurance is right up there with the toughest, as CSP executives will explain at the upcoming Software-Driven Operations summit in London.
The Eurasian operator has flipped its digital strategy to give greater autonomy to its geographically diverse operating companies.
Featured Video
Upcoming Live Events
November 5, 2019, London, England
November 7, 2019, London, UK
November 14, 2019, Maritim Hotel, Berlin
December 3-5, 2019, Vienna, Austria
December 3, 2019, New York, New York
March 16-18, 2020, Embassy Suites, Denver, Colorado
May 18-20, 2020, Irving Convention Center, Dallas, TX
All Upcoming Live Events