Palo Alto is a center of innovation and deserves a state-of-the-art next-generation mobile broadband network to meet the needs of its tech savvy residents and businesses. As home to hundreds of high tech businesses and data-hungry consumers, Palo Alto’s residents demand more from their networks.
Palo Alto’s topography presents challenges for wireless signals. Several factors — including hills, trees and buildings in the area — affect how wireless signals travel.
1. What is a DAS and how does it work?
A Distributed Antenna System, or DAS, is a network of smaller, spatially separated antenna nodes connected to the communications network.
A DAS network splits the transmitted signal among several smaller antennas to provide coverage and reliability over the same area as a single cell tower antenna. DAS networks are effective in areas with difficult topography, structural impediments (e.g. buildings, or within buildings), or in locations where, for a variety of reasons, it is not optimal to build a traditional macro sites.
2. What does a DAS look like?
3. Why DAS?
Microcell antennas of a DAS network are significantly smaller than the macrocell antenna of a cell tower, and its footprint is much smaller. A DAS allows for more widespread coverage because several sites can be deployed to more effectively cover an area of varied topography or large edifices.
A DAS can provide multiple service platforms (mobile broadband, mobile radios, pagers PCS, UMTS) and is effective for public safety alert systems.
4. Why do we need a DAS and what will it do for me?
Palo Alto’s unique topography, combined with its building density, pose a challenge to wireless network performance. Deploying a DAS network will increase network performance by providing greater coverage throughout the city and filling small gaps in existing coverage. AT&T’s DAS network will improve call quality and reliability while also supporting stronger signals, increased traffic and faster transfer of data.
5. What is the status of AT&T’s DAS deployment and when will it be completed?
AT&T submitted its application for wireless communications facilities to the City of Palo Alto on January 14, 2011. The application includes a detailed statement documenting our efforts to negotiate co-location with existing wireless facilities in the area, consideration of alternative project locations, statement justifying the need for the facilities, coverage maps and check lists. Additionally, the application requires a statement of aesthetic quality and location maps of the sites.
The public deserves and demands excellent mobile broadband service, and AT&T is ready to begin work as soon as the City accepts its application. AT&T is proposing a DAS throughout downtown Palo Alto.
6. Applications to the City of Palo Alto
AT&T submitted an application for wireless communications facilities to the City of Palo Alto on January 14 of 2011. That initial application has been superseded by an application for 20 DAS locations, filed on September 13, 2011. As before, the application includes a detailed statement documenting our efforts to negotiate co-location with existing wireless facilities in the area, consideration of alternative project locations, statement justifying the need for the facilities, coverage maps and check lists. Additionally, the application includes a statement of aesthetic quality and location maps of the sites.
The public deserves and demands excellent mobile broadband service, and AT&T’s DAS deployment has been engineered to provide improved coverage throughout Palo Alto. AT&T is committed to keeping residents informed about our plans in their neighborhoods, and is holding Open House meetings for residents who will benefit from nearby DAS sites. Please go to our Community Calendar page to find out more about AT&T’s Open House meetings.
Palo Alto oDAS Application 4th Plan Set Filed 06/29/2012:
ARB Design Drawings
Palo Alto oDAS Application 3rd Plan Set Filed 03/29/2012:
ARB Design Drawings
Palo Alto oDAS Application 2nd Plan Set Filed 03/06/2012:
ARB Design drawings:
Palo Alto oDAS Application 1st Plan Set Filed 09/13/2011:
ARB Design Drawings:
oDAS is a network of antennas and equipment connected to a common radio source that provides wireless telephone and data service within a specific geographical area. The equipment can be housed in a cabinet on the ground with its antennas mounted on a utility pole, street light or traffic signal, or can be built with both equipment and antennas mounted on a pole. Pole mounted equipment may include a power supply and meter, fiber splice box, oDAS cabinet (node), and battery cabinet, in addition to the antennas.
7. Why are you building this oDAS in my neighborhood?
Our oDAS will bring wireless telephone and data service closer to your home or office and improve wireless service coverage. It offers an alternative to macro wireless antenna towers.
8. I understand you are also proposing Wi-Fi in Palo Alto. Why are you proposing both Wi-Fi and oDAS?
Wifi service helps offload wireless data and thus can increase capacity on the wireless network.
9. Why is AT&T proposing both the St. Albert’s Church wireless cell tower and oDAS in our neighborhood?
In general, providing wireless service with a macro tower is normally a preferred deployment choice as it has the potential to provide service over an extended area from a single antenna site. This is the case with the St. Albert the Great Church site, which is a well-located site with a good opportunity for screening. Even after the St. Alberts macro cell tower is built, DAS can be helpful in filling coverage gaps caused by larger buildings, trees, and other obstructions, particularly in areas near the edge of the effective coverage of the cell site. In addition, there are not always good locations for macro sites, and oDAS can help fill in coverage in such areas as well. oDAS will bring service closer to your home using existing utility poles. AT&T will design the remaining oDAS locations in order to work with the effective coverage of all of its existing sites, including the St. Albert’s site once it is approved.
10. What’s involved in building this oDAS?
The first step in building an oDAS involves an analysis of the wireless telephone radio coverage of a large geographical area looking for gaps in coverage and capacity. After these gaps are found, wireless providers typically look for locations where an antenna tower might be constructed to provide the most coverage from a single installation. If, for various reasons, the gaps would be better filed by more localized and disbursed antennas (e.g., a bridge, tunnel or subway, high capacity outdoor areas, or areas involving limited or significantly obscured line of sight from buildings or trees) or a suitable site for an antenna tower is unavailable, oDAS alternatives can be pursued.
11. I don’t want this oDAS in my neighborhood? What other options are available?
Other options may include placing a macro antenna cell site near your neighborhood.
12. How many are you deploying in Palo Alto? How many homes are served by a cabinet (node)?
Serving capacity varies by cabinet and by the density of homes or business, geography and topology in a neighborhood.
Generally, an oDAS requires a cabinet mounted on a pole or on a concrete pad every 1/4 to 1/3 of a mile. AT&T has submitted the first 9 DAS sites in Palo Alto and is continuing to evaluate the design for oDAS throughout the rest of the community, and the final deployment will depend on required demand and city approval.
13. What happens if an underground utility district is established in my neighborhood?
The fact that there is an oDAS in the neighborhood would not affect any undergrounding efforts. We will request that our oDAS facilities be moved to nearby street lights, where available. And, of course, we will support and abide by all undergrounding codes and laws relocating aerial facilities to underground locations.
14. Will you be paying the city of Palo Alto to place your oDAS on the poles?
Yes. AT&T will pay the city for placing equipment on any city space on utility poles, and on city-owned street light standards. We are in discussion with the City of Palo Alto regarding this issue.
15. Did you purposely choose poles that are located in front of rental properties to avoid conflict with property owners?
No. Poles were chosen based on many factors. First, we looked for poles that would be properly spaced to provide effective coverage throughout the service gap area. Second, we looked for poles that had sufficient space to house the equipment easily and in compliance with all requirements and confirmed the pole was in good condition. Third, we looked for poles that would have easy access to fiber facilities and power in order to minimize construction disruption.
16. What happens when the cabinet (node) on the ground gets hit by a car?
If the damage is of the magnitude that causes the cabinet (node) to fail, an alarm will alert our Network Operations Center triggering a dispatch.
17. Why can’t you just co-locate on other carriers existing cell sites?
We do. If there were existing cell towers and infrastructure that would provide the necessary coverage, then we would be glad to attach to it.