TDD vs FDD ( Wimax / LTE )

[rilharri]

Ok i have read about both of these.

I know Sprint uses TDD Wimax, but why would anyone use FDD?

China is using TDD-LTE but Verizon is using FDD-LTE, FDD my give faster upload but it just seems like its a waste of freq to use FDD?

Anyone have some experience or details to help?

[hyperdog]

Only reason I could see using FDD is for faster throughput. Yes you are using alot more spectrum to attain faster speeds. More spectrum use = more interference.

[503ducati]

LTE-TDD & WiMAX: Two Peas in a Pod?

Link

A new whitepaper released by Intel (pdf) claims WiMAX technology is more spectrally efficient than HSPA or LTE. The report compares Mobile WiMAX with HSPA, HSPA+, and LTE. Intel says WiMAX can handle more subscribers per cell site with higher QOS.

According to the report, WiMAX is able to support 20 video streaming users per sector at 256 kbps, using a 10MHz channel, compared to 12 users at 128 kbps on an HSPA network. Furthermore, WiMAX networks are able to support a large number of users even with high monthly data usage of 12GB per subscriber.

[503ducati]

If the decision hasn't been made yet, before too long Clear/Sprint will have to decide long-term wither they go forward with WiMAX(802.16m) or an LTE-Advanced(E-UTRA) platform on their network for next generation 4G offerings.

[rilharri]

Take a look at this TDD-LTE

http://www.tmcnet.com/usubmit/2010/02/22/4636355.htm

Using 50 % less spectrum and getting the same speed..

Why would Verizon or anyone use FDD-LTE and waste spectrum

- China Mobile (00941.HK; CHL.NYSE)'s TD-LTE test network has achieved a record-high download speed of 80 Mbps, according to an officer from the company, who declined to be named.

The network realized the record speed on a 20 MHz channel. To reach a peak rate of 100 Mbps, the TD-LTE network requires only half the bandwidth needed by a FDD-LTE network.

[bigsnake49]

Take a look at this TDD-LTE

http://www.tmcnet.com/usubmit/2010/02/22/4636355.htm

Using 50 % less spectrum and getting the same speed..

Why would Verizon or anyone use FDD-LTE and waste spectrum

- China Mobile (00941.HK; CHL.NYSE)'s TD-LTE test network has achieved a record-high download speed of 80 Mbps, according to an officer from the company, who declined to be named.

The network realized the record speed on a 20 MHz channel. To reach a peak rate of 100 Mbps, the TD-LTE network requires only half the bandwidth needed by a FDD-LTE network.

AT&T and Verizon have no choice because the spectrum they won in the 700Mhz auction is FDD. Eventually they will offer vice on that spectrum thru VOIP. Voice is symmetrical, except when I'm talking to my wife. Then it's highly assymetrical.

[503ducati]

AT&T and Verizon have no choice because the spectrum they won in the 700Mhz auction is FDD. Eventually they will offer vice on that spectrum thru VOIP. Voice is symmetrical, except when I'm talking to my wife. Then it's highly assymetrical.

[rilharri]

Huge News

http://www.lightreading.com/document...treading_gnews

Clearwire LLC (Nasdaq: CLWR) is part of a group of operators and vendors that has asked the 3rd Generation Partnership Project (3GPP) standards body to start work on specs that would allow TD-LTE to be deployed in the US in the 2.6GHz spectrum -- which is now used for WiMax -- in a move that further exposes the operator's interest in the competing proto-4G standard.

The proposal to adopt the 2496MHz-to-2690MHz frequency band in the US for TD-LTE, which was first highlighted on the "LTE Watch" blog, was accepted at a 3GPP meeting earlier this month. The acceptance is significant because it will enable Clearwire and other spectrum holders to deploy TD-LTE, which is the time division duplex (TDD) version of LTE, in the US.

[503ducati]

http://www.fiercebroadbandwireless.c...max/2010-03-29

WiMAX operators will also be barely affected by TD-LTE in the short term. WiMAX is years ahead in terms of technological maturity, devices and ecosystem. This gives them a strong advantage in comparison to TD-LTE operators: They know the technology already, they have a network, and they have customers. They also have the choice whether to switch to TD-LTE or not--and, more importantly, they have no pressure to do so before TD-LTE has reached the maturity they feel comfortable with or until the WiMAX 16m prospects become clearer.

[offthegrid]

Could TDD-LTE be used on the Nextel spectrum in the future? Thats unpaired spectrum correct?

[bigsnake49]

Could TDD-LTE be used on the Nextel spectrum in the future? Thats unpaired spectrum correct?

No, the IDEN spectrum is paired spectrum. But there is nothing that prohibits them from implementing FDD-LTE on that spectrum for overlay purposes.

[rbsremodeling]

Clearwire and Sprint ask 3GPP for TDD-LTE U.S. std in 2.6GHz band
Wednesday, March 31, 2010

By Alan Weissberger

Introduction

Clearwire and Sprint are part of a group of operators and vendors that have asked the 3rd Generation Partnership Project (3GPP) standards body to start work on specs that would allow TD-LTE to be deployed in the US in the 2.6GHz spectrum — which is now used for mobile WiMAX in the U.S. The actual 3GPP contribution had many authors, with Clearwire, Sprint listed 1st (China Mobile also listed)


Link: http://viodi.com/2010/03/31/1835/

[offthegrid]

Is this 2.6 gig spectrum holdings included now when they say Clear has 150 gig of spectrum?

It almost sounds as though they have huge holdings that are not even considered when talking about current spectrum holdings.

Between all that and being able to do something with the Nextel spectrum down the road (if they have a need) Sprint seems to be well positioned for the long term.

[bigsnake49]

Is this 2.6 gig spectrum holdings included now when they say Clear has 150 gig of spectrum?

It almost sounds as though they have huge holdings that are not even considered when talking about current spectrum holdings.

Between all that and being able to do something with the Nextel spectrum down the road (if they have a need) Sprint seems to be well positioned for the long term.

I think that Sprint/Clear has plenty of spectrum. The SMR spectrum will most probably get repurposed to LTE voice when the time comes.

[reuthermonkey]

Is this 2.6 gig spectrum holdings included now when they say Clear has 150 gig of spectrum?

It almost sounds as though they have huge holdings that are not even considered when talking about current spectrum holdings.

Between all that and being able to do something with the Nextel spectrum down the road (if they have a need) Sprint seems to be well positioned for the long term.

Yep. This is one of the reasons it was rumored that Deutsche Telekom would purchase Sprint. At $12Bil, it's a relative bargain when only looking at its spectrum holdings. Of course, it has a lot of debt too...

Either way, Clear/Sprint has a lot of spectrum to play with for the future.