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Comment Re:Where the choke point really is (Score 5, Informative) 273

It doesn't quite work this way. This is going to be a bit technical, but you asked a technical question, so bear with me. Yes, I am a ham (since you asked for one), and I've also done some commercial RF data systems.

As others have pointed out, cellular telephone systems aren't like broadcast systems. You really can "put up more towers" to increase the amount of "service" (available data transfer per unit time, number of simultaneous voice calls, etc.) in a given geographic area without using more RF bandwidth. The reason for this is that you can turn the power on the base and handset down to reduce the coverage of the cell allowing reuse of the RF bandwidth more frequently within a certain geographical space. This is already done: cells on rural highways are much larger than cells within a city. In fact, the cells on rural highways would often be capable of covering an entire city from a geographic point of view, but there wouldn't be enough capacity to handle all that traffic, so smaller (lower power, lower antenna angle, etc.) cells are placed in cities allowing reuse of that RF bandwidth. Broadcast services can be thought of as "cellular" with very large cells (depending on the service, up to and including the entire planet for HF "shortwave" radio, for example) if you want, but that's not a traditional interpretation.

As for how much bandwidth it takes to attain a certain information rate, that varies with a number of factors. Assuming a uniform RF environment (noise, propagation, etc., which of course isn't true but is handy for discussion), the key tradeoff is made by how "aggressive" your modulation scheme is. A more aggressive modulation scheme packs more data into a certain amount of RF bandwidth, but it requires a stronger signal to noise ratio at the receiver to demodulate and recover the data. The exact relationship between how much data you can chuck into a given amount of RF bandwidth and the required receiver SNR varies with your chosen modulation scheme and receiver design. The reason data rates have been increasing with time is that newer, better (easier to demodulation) modulation schemes and better (mostly less noisy, but also more cost effective for a given complexity) receivers are being developed. More cells are also being added (see above) to lessen "competition" for the channel's bandwidth, but we're also seeing a lot more users and demand, so that probably averages out. The amount of RF bandwidth allocated to the cellular telephone services has remained roughly constant since the late 90s (800MHz cellular band + 1900MHz PCS band, though other bands are also used regionally, and some of these are new).

In a two-way scenario like a cellular telephone, you also get to play with the fact that the two directions don't behave equally. The base-to-handset link (downlink) has the advantage of no access contention (there's just one base, and it knows everything it's doing), expensive equipment (there's only one, so the company can pump some money into it), and lots of power available (it's plugged into the wall). The handset-to-base link (uplink) is messier: it has access contention (multiple handsets coordinated remotely by the base), cost sensitive equipment (consumers don't like to pay thousands of dollars for their handsets), and limited power (batteries). Antennas are something of a wash since antennas are effective about equally in both directions. What all this means is that it's easier to use a more aggressive modulation scheme (and hence cram more bits per second into a given chunk of RF MHz) on the downlink than the uplink. Fortunately, this is roughly in-line with consumer demand: most consumers want to transfer large stuff to their phones, not from them. FWIW, Cable Modems have similar concerns, and a similar situation results.

You also seem to assume a TDMA based uplink channel. Modern standards are all CDMA based. While the theory of operation is totally different, the effect is the same: multiple people contend for the same resource. Various standards allow for various amounts of "resource concatenation" to allow one user to use more than one "unit" of the uplink when it's not full, but most of them do not dynamically adjust the size of the quantum. (Though, somewhat amusingly, the downlink of CDMA2000 EVDO is time-division multiplexed).

Cell providers also have to ensure that old handsets are supported. For non-compatible upgrades (e.g. GSM to UMTS - done by AT&T and T-Mobile), this means they basically have to run both standards side-by-side on different channels. This results in some interesting scenarios where congestion will force some users onto a slower, less efficient standard even if the handset and base both support something better. I've seen this happen at amusement parks a lot.

Also, some on-air standards don't support voice calls at all (e.g. EVDO or HSDPA), and the carriers always want to be able to handle voice calls, so generally at least one channel on a cell will operate in a voice capable mode, though I can imagine some might have the capability to drop every channel into a data-only mode if there really are no voice calls. A true "4G" service would eliminate this as voice calls are actually just data, as far as the infrastructure is concerned, with QoS used to ensure availability. Current data standards (including the LTE being deployed by Verizon) do not have this QoS capability, so voice calls are still routed on a separate channel (probably RTT, but I'm not familiar enough with these deployments to say this authoritatively). LTE Advanced should mash all this back together.

Of course, all this stuff has limits. It's not practical to set up a cell (with the required base station, antennas, tower, etc.) every 100 feet, and current RF technology and transmitter/receiver complexity is only so advanced, so there is a limited amount of service available to an end user. I can't say I agree with Verizon's pricing (I use Sprint, and while I don't have a 4G handset, if I did, I'd have unlimited transfer while on 4G Wi-Max and a 5GB soft cap while on 3G EVDO/RTT), it's not like they could offer unlimited everything easily. I just think the overage charges and base limits are a little off.

(I apologize if I've gotten any technical details e.g. what standard supports what wrong - I'm not a cellular engineer, so if anyone reading this is, please correct me. The basics should be reasonable, though)


Submission + - Japan to Fingerprint, Photograph all Foreigners (theage.com.au)

MochaMan writes: "As of this Tuesday, November 20th, Japan will be requiring mandatory fingerprinting and mug shots of all foreigners entering the country, making it one of only two countries in the world to do so. The program goes further than the US program in that it also applies to visa-holders and permanent residents. The prints will be stored and shared with other governments. The Japanese government has produced an explanatory video, and even a promotional PDF poster. Japanese and international civil rights groups have raised concerns that the practice is both an invasion of privacy and discriminatory. An online petition to abolish the program is available. Is the age of privacy over?"
First Person Shooters (Games)

Submission + - UT3 on Linux or Mac Anyone?

Space-Nut writes: It is well known that the Unreal Tournament series have tried hard in the past to make their games available for Linux and Macs. With the upcoming Unreal Tournament 3 release sometime soon and a statement back in May from Mark Rein in thread about DX10"..All this means is that UT3 will support DX10 — it does NOT mean that DX10 is required! We expect the vast majority of our users will be Windows XP / DX9 users. We will also support Mac and Linux as per usual." Is anyone else really excited about UT3 and 2007 and will you support Epic in providing a Linux and Mac version by buying the game?

Comment Re:This is a gaming enthusiast's dream... (Score 4, Informative) 76

It's not unheard of in the world of Music games at all, which may explain why the genre has trouble with the US market. If you're familiar with Konami's Bemani series (which, I might add, has much of this functionality since Guitar Freaks and Drum Mania can be linked, and are in fact on the same disc when sold for the home market), expensive controllers are the way things work. A beatmania controller is about 7000Yen (~$70US) in Japan, and pop'n mini controllers are comparable. If you want *good* (so-called "Arcade Style"), full arcade size controllers, you can expect to drop upwards of $300 on a single controller for these games. A good controller for Drum Mania (a MIDI drum set) can cost over $1000! Even a cheap-o DDR pad will run you $25 here in the US. A good one is usually in the $75-120 range for foam insert based ones, and $200+ for a sturdy metal one.

The Japanese are more gadget oriented than USians, though, and this may explain at least some of the success of the series in the Japanese market as compared with its difficulty here in the USA.
The Courts

Submission + - RIAA sues paralyzed stroke victim

Waylon writes: "It seems the RIAA will sue anyone, anywhere, even if you're a paralyzed stroke victim. Yes, Warner Music and the RIAA are suing a retired railroad man in Florida whose left side has been paralyzed by a stroke and whose sole source of income is his disability check. From the article: "Although the defendant John Paladuk, an employee of C&N Railroad for 36 years, was living in Florida at the time of the alleged copyright suit, and had notified the RIAA that he had not engaged in any copyright infringement, and despite that the fact that Mr. Paladuk suffered a stroke last year which resulted in complete paralysis of his entire left side and severely impaired speech, rendering him disabled, and despite the fact that his disability check is his sole source of income, the RIAA commenced suit against him on February 27, 2007.""

Submission + - Linux Kernel Devs Offer Free Driver Development

schwaang writes: Linux Kernel hacker Greg Kroah-Hartman, author of Linux Kernel in a Nutshell has posted an epic announcement on his blog:

"the Linux kernel community is offering all companies free Linux driver development. [...] All that is needed is some kind of specification that describes how your device works, or the email address of an engineer that is willing to answer questions every once in a while."

"If your company is worried about NDA issues surrounding your device's specifications, we have arranged a program [...] in order to properly assure that all needed NDA requirements are fulfilled."

"Now your developers will have more time to work on drivers for all of the other operating systems out there, and you can add "supported on Linux" to your product's marketing material."

This could portend increased device compatibility for Linux users, higher-quality drivers, and fewer non-free binary blobs.

P.S. nvidia this means you!
The Internet

Submission + - Hosting Provider Builds Own Power Substation

1sockchuck writes: "With data centers using more and more power, Sacramento managed hosting provider RagingWire wanted to ensure that its customers wouldn't run out of juice. So the company built its own 69kV power substation on its property, which will supply its data center with up to 46 megawatts — enough to power about 25,000 single-family homes. Concerns about the availability of electricity for data center prompted a Silicon Valley "power summit" last month. Is this a sign of things to come?"

Submission + - Windows XP Activation in the Future?

bigredswitch writes: Now we're on the verge of Vista being released, how are we going to activate XP when Microsoft drop support, either when performing a reinstall or resurrecting old hardware? It's not going to be a problem now or for the next few years, sure, but what's the future going to be like (flying cars aside)? Getting an older machine back into action to pull files off, run machine automation, etc., is easy with Win2k and everything that went before (I've worked at places running Gem on 286s still for in-house stuff) but is this at an end with XP and onwards? How are other people looking to handle this?
It's funny.  Laugh.

Submission + - A Blogger gets an "Un-Cease and disist" no

AlphaLop writes: A blogger who wrote a somewhat Derogatory article about the online "Game" Second Life and created a link on his blog inviting lawsuits got an unexpected response from Linden Lab...

Too bad the RIAA and MPAA don't think this way.... http://news.yahoo.com/s/ap/20070124/ap_on_hi_te/se cond_life_parody Sorry for not embedding the link but I don't know HTML yet.
XBox (Games)

Submission + - What are these 360 ports for?

jwigum writes: "So I got to wondering: What are those two ports on the bottom of a 360 controller used for? The ports in question(second photobucket file here in case the first dies) obviously have contacts. The thing that puzzles me is that the only peripheral I know of that uses these ports is the stock 360 headset. I've included that in the same picture, but flipped upside down so that the area that would be in contact with the... contacts is visible. As you can see, there aren't any contacts there. I can only assume they're for a peripheral that is either unreleased, or abandoned(stereo sound headphones for split screen?).

So Slashdot: What are these ports for?"

Submission + - Time for a different terminal emulator?

swankjesse writes: "I spend a lot of time at the command line, so a good terminal emulator is important to me. Unfortunately, the default ones all have some annoyances:
Konsole inserts extra newline characters in the output, which makes it labour-intensive to do cut-and-paste.
Gnome Terminal doesn't let me scroll back while output is being generated.
Terminal.app doesn't have tabs, so I'm constantly having to search for my window. And it's Mac-only.

So I started searching for a better terminal emulator. The most interesting thus far is Terminator. It's got horizontal scrolling, which is ideal for SQL. And it gets the details right: scrollback, wrapping, fonts and keyboard shortcuts Just Work.

What's terminal emulator do you use? What does it do better?"

Submission + - Sega to stop GD-ROM production

Joan Cross writes: Sega of Japan plans to discontinue production of GD-ROM media in February, 2007. This media is used almost exclusively by the Sega Dreamcast home console, and the NAOMI arcade system. By stopping production, future official games (licensed by Sega) on the Dreamcast or NAOMI will not be possible. The Dreamcast Community are asking all fans past and present to help keep alive the Dream.

Submission + - PCI SIG releases PCIe 2.0

symbolset writes: "According to The Register PCI SIG has released version 2.0 of the PCI Express base specification.
The new released doubles the signalling rate from 2.5Gbps to 5Gbps. The upshot: a x16 connector can transfer data at up to around 16GBps.
The PCI-SIG release is here. The electromechanical specification is also due to be released shortly:
The companion PCI Express Card Electromechanical 2.0 specification is currently at revision 0.9, having completed its 60-day member review. The PCI-SIG anticipates that this specification too will be released in the near future.

Submission + - Water contest for a Wii kills

priestx writes: A Californian woman who took part in a water-drinking contest to win a video game system has died of water intoxication, tests have shown. Jennifer Strange had taken part in the "Hold Your Wee for a Wii" game run by KDND 107.9 radio in Sacramento, which promised the winner a Nintendo Wii. A work colleague said Ms Strange had reported her head was hurting hours after the contest and was going home.

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