Friday, October 01, 2004

San Diego CHP & Caltrans comm center

San Diego CHP & Caltrans communications center. Nice HF log periodic antenna for backup when microwaves can't get through the smog & smoke ;-)

Tuesday, September 14, 2004

FCC limits antennas on historical sites

RCR Wireless News: The FCC has adopted rules to restrict placement of antennas upon historical resources. "The FCC recognized that, as the number of tower constructions around the country has dramatically increased since the late 1990s, it has a responsibility to manage the expansion of communications infrastructure in a way that best preserves our nation's historical resources", said the commission. Commissioners Abernathy and Martin partially dissented, questioning the FCC's authority under the the National Historic Preservation Act.

Tuesday, September 07, 2004

Multiple-in, multiple-out (MIMO) antennas for wi-fi

New Wi-Fi standards (802.11n) will likely include Multiple-in, multiple-out (MIMO) antennas for 100 Mbps throughput and increased range.
Network Magazine | Boosting Wi-Fi With MIMO and 802.11n | August 1, 2004: "Multiple-In, Multiple-Out (MIMO), which is likely to be 802.11n's foundation"

Friday, September 03, 2004

Raining Satellite Dishes in Bahamas this AM

It was raining satellite dishes in Nassau last night when hurricane Frances hit. The popularity of direct broadcast satellite dishes, half-assed self-installation, large wind profile, and flying saucer aerodynamics combined to create quite a mess. : Hurricane Frances Hits Bahamas

Tuesday, August 31, 2004

Mobile HF antenna on CDMAONE

A hitch-mounted amateur radio high frequency (HF) antenna. Note "CDMA ONE" license place. Qualcomm employee?

Stealth Flagpole antenna

Stealth flagpole antenna on the west side of the 163 freeway South of Friars Road. On the Remington College "Campus". Note radome housing antennas at top. What happens when the flag gets wet? Reduction of signal in direction of the wind? Well, it never rains in San Diego anyway.

Looking up from base.

The base of the flagpole antenna.

This one is a "Minimum Visual Impact Structure" manufactured by Valmont . They also make stealth palm tree, pine tree and cactus antennas.

Monday, August 30, 2004

Verizon cell tower #1012628

Verizon cell tower #1012628

According to the FCC Antenna Structure Registration (ASR) database, this monopole is Verizon's tallest cell tower in San Diego at 50.9 meters above ground. It appears to be hosting cellular on the top tier, PCS on the lower tier and a few microwave backhaul links to other cell towers. A thing of beauty and an eyesore.

Lower PCS tier

Upper cellular tier.

Base of tower

Looking up at tower and exposed hardline coaxial RF cables.

Door to "secure" blockhouse. Note hinges on the outside of door ;-)

Mandatory FCC antenna structure registration number.

The tower is near a public elementary school (behind the photographer) and a private school in the foreground.

Friday, August 27, 2004

Utility Pole Antennas

A toddler, a baby and a puppy. They all do better when you take them outside for a walk from time to time. It's amazing the things you notice walking. Walking instead speeding at 40 MPH through your 25 MPH neighborhood. I've been noticing antennas.

Lets begin our little journey with telephone poles. Ok, utility poles. They are now sprouting antennas of various types. We are really loading up these poor, dead, tar-covered trees.

The photos below were taken within a 1 mile stretch near Palos Verdes Drive North in Palos Verdes Estates, CA.

Cellular sector antennas (painted brown) pointing at Palos Verdes Country Club and Palos Verdes Dr. N. Also note the three small white antennas and radio connected directly to cable. I believe this is an "old" Cox communications PCS cell. Cox Communications sold their PCS business to Sprint. These Cox cable-attached trio antennas are everywhere around Palos Verdes Estates. I suspect they are not in use. Anyone know the story?

Sector antennas aimed at Palos Verdes Drive North. I believe this is Sprint wideband PCS. Also see what looks like an old Ricochet antenna above the PCS antennas.


This pole is between two houses, within four feet of a driveway. It might be worth changing wireless providers when there is a cell in your front yard.

Close-up. Time to trim the tree.

This picture is a bit underexposed, but you can see the silhouette of the two Sprint PCS isopole antennas on the right side of the pole and the three old Cox antennas on the cable to the left. This is a Sprint PCS site. There is a phone number for the Sprint Network Operations Center (NOC) on the equipment.

Close-up of the radios mounted on the pole at a height of 7'. I'm surprised by how vulnerable this cell site is. RF cabling is exposed within arm's reach.

So, I'm not surprised to see so many of these micro cells popping up, that was always the vision for cellular communications systems... smaller, lower-level cells as the needs for capacity grow. I am surprised by how physically insecure these cells are. I am surprised that the antennas have trees in their radiation path, that's a problem at 1.9GHz. I guess the cellular providers just have to live with trees in residential areas.