E-UTRA

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EUTRAN architecture as part of a LTE and SAE network

e-UTRA is the air interface of 3GPP's Long Term Evolution (LTE) upgrade path for mobile networks. It is an acronym for evolved UMTS Terrestrial Radio Access, also referred to as the 3GPP work item on the Long Term Evolution (LTE)[1] also known as the Evolved Universal Terrestrial Radio Access (E-UTRA) in early drafts of the 3GPP LTE specification.[1] E-UTRAN is the initialism of Evolved UMTS Terrestrial Radio Access Network and is the combination of E-UTRA, UEs and EnodeBs.

It is a radio access network standard meant to be a replacement of the UMTS and HSDPA/HSUPA technologies specified in 3GPP releases 5 and beyond. Unlike HSPA, LTE's E-UTRA is an entirely new air interface system, unrelated to and incompatible with W-CDMA. It provides higher data rates, lower latency and is optimized for packet data. It uses OFDMA radio-access for the downlink and SC-FDMA on the uplink. Trials started in 2008.

Features[edit]

EUTRAN has the following features:

  • Peak download rates of 299.6 Mbit/s for 4×4 antennas, and 150.8 Mbit/s for 2×2 antennas with 20 MHz of spectrum. LTE Advanced supports 8×8 antenna configurations with peak download rates of 2,998.6 Mbit/s in an aggregated 100 MHz channel.[2]
  • Peak upload rates of 75.4 Mbit/s for a 20 MHz channel in the LTE standard, with up to 1,497.8 Mbit/s in an LTE Advanced 100 MHz carrier.[2]
  • Low data transfer latencies (sub-5 ms latency for small IP packets in optimal conditions), lower latencies for handover and connection setup time.
  • Support for terminals moving at up to 350 km/h or 500 km/h depending on the frequency band.
  • Support for both FDD and TDD duplexes as well as half-duplex FDD with the same radio access technology
  • Support for all frequency bands currently used by IMT systems by ITU-R.
  • Flexible bandwidth: 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz and 20 MHz are standardized. By comparison, W-CDMA uses fixed size 5 MHz chunks of spectrum.
  • Increased spectral efficiency at 2–5 times more than in 3GPP (HSPA) release 6
  • Support of cell sizes from tens of meters of radius (femto and picocells) up to over 100 km radius macrocells
  • Simplified architecture: The network side of EUTRAN is composed only by the enodeBs
  • Support for inter-operation with other systems (e.g., GSM/EDGE, UMTS, CDMA2000, WiMAX, etc.)
  • Packet switched radio interface.

Rationale for E-UTRA[edit]

Although UMTS, with HSDPA and HSUPA and their evolution, deliver high data transfer rates, wireless data usage is expected to continue increasing significantly over the next few years due to the increased offering and demand of services and content on-the-move and the continued reduction of costs for the final user. This increase is expected to require not only faster networks and radio interfaces but also higher cost-efficiency than what is possible by the evolution of the current standards. Thus the 3GPP consortium set the requirements for a new radio interface (EUTRAN) and core network evolution (System Architecture Evolution SAE) that would fulfill this need.

These improvements in performance allow wireless operators to offer quadruple play services - voice, high-speed interactive applications including large data transfer and feature-rich IPTV with full mobility.

Starting with the 3GPP Release 8, e-UTRA is designed to provide a single evolution path for the GSM/EDGE, UMTS/HSPA, CDMA2000/EV-DO and TD-SCDMA radio interfaces, providing increases in data speeds, and spectral efficiency, and allowing the provision of more functionality.

Architecture[edit]

EUTRAN consists only of enodeBs on the network side. The enodeB performs tasks similar to those performed by the nodeBs and RNC (radio network controller) together in UTRAN. The aim of this simplification is to reduce the latency of all radio interface operations. eNodeBs are connected to each other via the X2 interface, and they connect to the packet switched (PS) core network via the S1 interface.[3]

EUTRAN protocol stack[edit]

EUTRAN protocol stack

The EUTRAN protocol stack consist of:[3]

  • Physical layer:[4] Carries all information from the MAC transport channels over the air interface. Takes care of the link adaptation (AMC), power control, cell search (for initial synchronization and handover purposes) and other measurements (inside the LTE system and between systems) for the RRC layer.
  • MAC:[5] The MAC sublayer offers a set of logical channels to the RLC sublayer that it multiplexes into the physical layer transport channels. It also manages the HARQ error correction, handles the prioritization of the logical channels for the same UE and the dynamic scheduling between UEs, etc..
  • RLC:[6] It transports the PDCP's PDUs. It can work in 3 different modes depending on the reliability provided. Depending on this mode it can provide: ARQ error correction, segmentation/concatenation of PDUs, reordering for in-sequence delivery, duplicate detection, etc...
  • PDCP:[7] For the RRC layer it provides transport of its data with ciphering and integrity protection. And for the IP layer transport of the IP packets, with ROHC header compression, ciphering, and depending on the RLC mode in-sequence delivery, duplicate detection and retransmission of its own SDUs during handover.
  • RRC:[8] Between others it takes care of: the broadcast system information related to the access stratum and transport of the non-access stratum (NAS) messages, paging, establishment and release of the RRC connection, security key management, handover, UE measurements related to inter-system (inter-RAT) mobility, QoS, etc..

Interfacing layers to the EUTRAN protocol stack:

  • NAS:[9] Protocol between the UE and the MME on the network side (outside of EUTRAN). Between others performs authentication of the UE, security control and generates part of the paging messages.
  • IP

Physical layer (L1) design[edit]

E-UTRA uses orthogonal frequency-division multiplexing (OFDM), multiple-input multiple-output (MIMO) antenna technology depending on the terminal category and can use as well beamforming for the downlink to support more users, higher data rates and lower processing power required on each handset.[10]

In the uplink LTE uses both OFDMA and a precoded version of OFDM called Single-Carrier Frequency-Division Multiple Access (SC-FDMA) depending on the channel. This is to compensate for a drawback with normal OFDM, which has a very high peak-to-average power ratio (PAPR). High PAPR requires more expensive and inefficient power amplifiers with high requirements on linearity, which increases the cost of the terminal and drains the battery faster. For the uplink, in release 8 and 9 multi user MIMO / Spatial division multiple access (SDMA) is supported; release 10 introduces also SU-MIMO.

In both OFDM and SC-FDMA transmission modes a cyclic prefix is appended to the transmitted symbols. Two different lengths of the cyclic prefix are available to support different channel spreads due to the cell size and propagation environment. These are a normal cyclic prefix of 4.7 µs, and an extended cyclic prefix of 16.6µs.

LTE Resource Block in time and frequency domains: 12 subcarriers, 0.5 ms timeslot (normal cyclic prefix).

LTE supports both Frequency-division duplex (FDD) and Time-division duplex (TDD) modes. While FDD makes use of paired spectra for UL and DL transmission separated by a duplex frequency gap, TDD splits one frequency carrier into alternating time periods for transmission from the base station to the terminal and viceversa. Both modes have their own frame structure within LTE and these are aligned with each other meaning that similar hardware can be used in the base stations and terminals to allow for economy of scale. The TDD mode in LTE is aligned with TD-SCDMA as well allowing for coexistence. These days, a single chipset can support both TDD-LTE and FDD-LTE operating modes.

The LTE transmission is structured in the time domain in radio frames. Each of these radio frames is 10 ms long and consists of 10 sub frames of 1 ms each. For non-MBMS subframes, the OFDMA sub-carrier spacing in the frequency domain is 15 kHz. Twelve of these sub-carriers together allocated during a 0.5 ms timeslot are called a resource block.[11] A LTE terminal can be allocated, in the downlink or uplink, a minimum of 2 resources blocks during 1 subframe (1 ms).[12]

All L1 transport data is encoded using turbo coding and a contention-free quadratic permutation polynomial (QPP) turbo code internal interleaver.[13] L1 HARQ with 8 (FDD) or up to 15 (TDD) processes is used for the downlink and up to 8 processes for the UL

EUTRAN physical channels and signals[edit]

Downlink (DL)[edit]

In the downlink there are several physical channels:[14]

  • The Physical Downlink Control Channel (PDCCH) carries between others the downlink allocation information, uplink allocation grants for the terminal.
  • The Physical Control Format Indicator Channel (PCFICH) used to signal the length of the PDCCH.
  • The Physical Hybrid ARQ Indicator Channel (PHICH) used to carry the acknowledges from the uplink transmissions.
  • The Physical Downlink Shared Channel (PDSCH) is used for L1 transport data transmission. Supported modulation formats on the PDSCH are QPSK, 16QAM and 64QAM.
  • The Physical Multicast Channel (PMCH) is used for broadcast transmission using a Single Frequency Network
  • The Physical Broadcast Channel (PBCH) is used to broadcast the basic system information within the cell

And the following signals:

  • The synchronization signals (PSS and SSS) are meant for the UE to discover the LTE cell and do the initial synchronization.
  • The reference signals (cell specific, MBSFN, and UE specific) are used by the UE to estimate the DL channel.
  • Positioning reference signals (PRS), added in release 9, meant to be used by the UE for OTDOA positioning (a type of multilateration)

Uplink (UL)[edit]

In the uplink there are three physical channels:

  • Physical Random Access Channel (PRACH) is used for initial access and when the UE losses its uplink synchronization,[15]
  • Physical Uplink Shared Channel (PUSCH) carries the L1 UL transport data together with control information. Supported modulation formats on the PUSCH are QPSK, 16QAM and depending on the user equipment category 64QAM. PUSCH is the only channel, which because of its greater BW, uses SC-FDMA
  • Physical Uplink Control Channel (PUCCH) carries control information. Note that the Uplink control information consists only on DL acknowledges as well as CQI related reports as all the UL coding and allocation parameters are known by the network side and signaled to the UE in the PDCCH.

And the following signals:

  • Reference signals (RS) used by the enodeB to estimate the uplink channel to decode the terminal uplink transmission.
  • Sounding reference signals (SRS) used by the enodeB to estimate the uplink channel conditions for each user to decide the best uplink scheduling.

User Equipment (UE) categories[edit]

3GPP Release 8 defines five LTE user equipment categories depending on maximum peak data rate and MIMO capabilities support. With 3GPP Release 10, which is referred to as LTE Advanced, three new categories have been introduced, and two more with 3GPP Release 11.[2]

User equipment category Maximum L1 datarate downlink Maximum number of DL MIMO layers Maximum L1 datarate uplink 3GPP release
Category 0 1.0 Mbit/s 1 1.0 Mbit/s Release 12
Category 1 10.3 Mbit/s 1 5.2 Mbit/s Release 8
Category 2 51.0 Mbit/s 2 25.5 Mbit/s Release 8
Category 3 102.0 Mbit/s 2 51.0 Mbit/s Release 8
Category 4 150.8 Mbit/s 2 51.0 Mbit/s Release 8
Category 5 299.6 Mbit/s 4 75.4 Mbit/s Release 8
Category 6 301.5 Mbit/s 2 or 4 51.0 Mbit/s Release 10
Category 7 301.5 Mbit/s 2 or 4 102.0 Mbit/s Release 10
Category 8 2,998.6 Mbit/s 8 1,497.8 Mbit/s Release 10
Category 9 452.2 Mbit/s 2 or 4 51.0 Mbit/s Release 11
Category 10 452.2 Mbit/s 2 or 4 102.0 Mbit/s Release 11

Note: Maximum datarates shown are for 20 MHz of channel bandwidth. Maximum datarates will be lower if less bandwidth is utilized.

Note: These are L1 transport data rates not including the different protocol layers overhead. Depending on cell BW, cell load, network configuration, the performance of the UE used, propagation conditions, etc. practical data rates will vary.

Note: The 3.0 Gbit/s / 1.5 Gbit/s data rate specified as Category 8 is near the peak aggregate data rate for a base station sector. A more realistic maximum data rate for a single user is 1.2 Gbit/s (downlink) and 600 Mbit/s (uplink).[16] Nokia Siemens Networks has demonstrated downlink speeds of 1.4 Gbit/s using 100 MHz of aggregated spectrum.[17]

EUTRAN releases[edit]

As the rest of the 3GPP standard parts E-UTRA is structured in releases.

  • Release 8, frozen in 2008, specified the first LTE standard
  • Release 9, frozen in 2009, included some additions to the physical layer like dual layer (MIMO) beam-forming transmission or positioning support
  • Release 10, frozen in 2011, introduces to the standard several LTE Advanced features like carrier aggregation, uplink SU-MIMO or relays, aiming to a considerable L1 peak data rate increase.

All LTE releases have been designed so far keeping backward compatibility in mind. That is, a release 8 compliant terminal will work in a release 10 network, while release 10 terminals would be able to use its extra functionality.

Frequency bands and channel bandwidths[edit]

From Tables 5.5-1 "E-UTRA Operating Bands" and 5.6.1-1 "E-UTRA Channel Bandwidth" of 3GPP TS 36.101,[18][19] the following table lists the specified frequency bands of LTE and the channel bandwidths each listed band supports:

E-UTRA
operating
band
Uplink (UL)
BS receive
UE transmit (MHz)
Downlink (DL)
BS transmit
UE receive (MHz)
Duplex
mode
Channel
bandwidths
(MHz)
Common name Frequency
band
(MHz)
Duplex spacing (MHz)
1 1920 – 1980 2110 – 2170 FDD 5, 10, 15, 20 IMT 2100 190
2 1850 – 1910 1930 – 1990 FDD 1.4, 3, 5, 10, 15, 20 PCS 1900 80
3 1710 – 1785 1805 – 1880 FDD 1.4, 3, 5, 10, 15, 20 DCS 1800 95
4 1710 – 1755 2110 – 2155 FDD 1.4, 3, 5, 10, 15, 20 AWS (AWS-1) 1700 400
5 824 – 849 869 – 894 FDD 1.4, 3, 5, 10 CLR 850 45
6 830 – 840 875 – 885 FDD 5, 10 UMTS 800 (replaced by band 19) 850 45
7 2500 – 2570 2620 – 2690 FDD 5, 10, 15, 20 IMT-E 2600 120
8 880 – 915 925 – 960 FDD 1.4, 3, 5, 10 E-GSM 900 45
9 1749.9 – 1784.9 1844.9 – 1879.9 FDD 5, 10, 15, 20 UMTS 1700 / Japan DCS
(subset of band 3)
1800 95
10 1710 – 1770 2110 – 2170 FDD 5, 10, 15, 20 Extended AWS
(superset of band 4)
1700 400
11 1427.9 – 1447.9 1475.9 – 1495.9 FDD 5, 10 Lower PDC 1500 48
12 699 – 716 729 – 746 FDD 1.4, 3, 5, 10 Lower SMH blocks A/B/C 700 30
13 777 – 787 746 – 756 FDD 5, 10 Upper SMH block C 700 −31
14 788 – 798 758 – 768 FDD 5, 10 Upper SMH block D 700 −30
15 1900 – 1920 2600 – 2620 FDD 5, 10 Reserved 700
16 2010 – 2025 2585 – 2600 FDD 5, 10, 15 Reserved 575
17 704 – 716 734 – 746 FDD 5, 10 Lower SMH blocks B/C
(subset of band 12)
700 30
18 815 – 830 860 – 875 FDD 5, 10, 15 Japan lower 800 850 45
19 830 – 845 875 – 890 FDD 5, 10, 15 Japan upper 800
(superset of band 6)
850 45
20 832 – 862 791 – 821 FDD 5, 10, 15, 20 EU Digital Dividend 800 −41
21 1447.9 – 1462.9 1495.9 – 1510.9 FDD 5, 10, 15 Upper PDC 1500 48
22 3410 – 3490 3510 – 3590 FDD 5, 10, 15, 20 3500 100
23 2000 – 2020 2180 – 2200 FDD 1.4, 3, 5, 10, 15, 20 S-Band (AWS-4) 2000 180
24 1626.5 – 1660.5 1525 – 1559 FDD 5, 10 L-Band (US) 1600 −101.5
25 1850 – 1915 1930 – 1995 FDD 1.4, 3, 5, 10, 15, 20 Extended PCS
(superset of band 2)
1900 80
26 814 – 849 859 – 894 FDD 1.4, 3, 5, 10, 15 Extended CLR
(superset of bands 5, 6, 18 and 19)
850 45
27 807 – 824 852 – 869 FDD 1.4, 3, 5, 10 SMR
(adjacent to band 5)
850 45
28 703 – 748 758 – 803 FDD 3, 5, 10, 15, 20 APT 700 55
29 N/A 717 – 728 FDD 3, 5, 10 Lower SMH blocks D/E
(Carrier Aggregation with band 2/4/23/30 only)
700 N/A
30 2305 – 2315 2350 – 2360 FDD 5, 10 WCS blocks A/B 2300 45
31 452.5 – 457.5 462.5 – 467.5 FDD 1.4, 3, 5 450 10
32 N/A 1452 – 1496 FDD 5, 10, 15, 20 L-Band
(Carrier Aggregation with band 20 only)
1400 N/A
not assigned 1915 – 1920 1995 – 2000 FDD AWS-2 (EPCS Block H)
(adjacent to band 25)
1900 80
not assigned 1755 – 1780 2155 – 2180 FDD AWS-3 (adjacent to band 4) 1700 400
study item 1980 – 2010 2170 – 2200 FDD MSS (adjacent to band 1) 2100 190
33 1900 – 1920 TDD 5, 10, 15, 20 Pre-IMT
(subset of band 39)
2100
34 2010 – 2025 TDD 5, 10, 15 IMT 2100
35 1850 – 1910 TDD 1.4, 3, 5, 10, 15, 20 PCS (Uplink) 1900
36 1930 – 1990 TDD 1.4, 3, 5, 10, 15, 20 PCS (Downlink) 1900
37 1910 – 1930 TDD 5, 10, 15, 20 PCS (Duplex spacing) 1900
38 2570 – 2620 TDD 5, 10, 15, 20 IMT-E (Duplex Spacing)
(subset of band 41)
2600
39 1880 – 1920 TDD 5, 10, 15, 20 DCS-IMT gap 1900
40 2300 – 2400 TDD 5, 10, 15, 20 2300
41 2496 – 2690 TDD 5, 10, 15, 20 BRS / EBS 2500
42 3400 – 3600 TDD 5, 10, 15, 20 3500
43 3600 – 3800 TDD 5, 10, 15, 20 3700
44 703 – 803 TDD 3, 5, 10, 15, 20 APT 700

Deployments by region[edit]

The following table shows the standardized LTE bands and their regional use. The main LTE bands are in bold print.

  • Networks on LTE-bands 1, 3, 7, 28 (FDD-LTE) or 38, 40 (TDD-LTE) are suitable for future global roaming in ITU Regions 1, 2 and 3.
  • Networks on LTE-band 8 (FDD-LTE) may allow global roaming in the future (ITU Regions 1, 2 and 3) (Long-term perspective).
  • Networks on LTE-band 20 (FDD-LTE) are suitable for roaming in ITU Region 1 (EMEA) only.
  • Networks on LTE-bands 2 and 4 (FDD-LTE) are suitable for roaming in ITU Region 2 (Americas) only.
Operating band Frequency band Common name North America Latin America Europe Asia Africa Oceania
01 2100 IMT No No Czech Republic (Vodafone) Japan (au, NTT Docomo, SoftBank Mobile), Philippines (Smart), South Korea (LG U+), Tajikistan (Babilon Mobile), Thailand (DTAC, TrueMove-H) Angola (Unitel) (no deployments)
02 1900 PCS A-F USA (AT&T, C Spire, T-Mobile) Dominican Republic (Tricom), Guatemala (Movistar), Paraguay (Personal), Peru (Claro), Uruguay (Movistar) No No No No
03 1800 DCS No Aruba (SETAR), Brazil (Nextel), Cayman Islands (Digicel Cayman), Costa Rica (Claro, Movistar), Dominican Republic (Orange), Venezuela (Digitel GSM) Yes Yes Yes Yes
04 1700 AWS A-F Yes Yes No No No No
05 850 CLR USA (U.S. Cellular) (no deployments) No South Korea (LG U+, SK Telecom) No Australia (Vodafone)
06 800 No No No replaced by band 19 No No
07 2600 IMT-E Canada (Bell, Rogers) Yes Yes Yes Ghana (Surfline), Zambia (MTN, Zamtel) Australia (Optus, Telstra (in Trial)), New Zealand (Spark) (in Trial)
08 900 E-GSM No No Czech Republic (Vodafone (temporary)[20][21]) South Korea (KT), Japan (SoftBank), Taiwan (Ambit Microsystems Corp, Chunghwa Telecom, Taiwan Star Cellular) (planned) (no deployments) Australia (Telstra) (in Trial)
09 1700 No No No Japan (E MOBILE, NTT Docomo)
(compatible with band 3)
No No
10 1700 EAWS A-G (no deployments) (no deployments) No No No No
11 1500 LPDC No No No Japan (au) No No
12 700 LSMH A/B/C USA (Regional carriers, U.S. Cellular, T-Mobile) No No No No Kiribati (TSKL)
13 700 USMH C Canada (EastLink, Feenix Wireless, MTS, SaskTel, Telus, Vidéotron Mobile) (planned), USA (Verizon) Bolivia (Entel Bolivia) No No No No
14 700 USMH D USA (Public Safety) No No No No No
15 No No Reserved No No No
16 No No Reserved No No No
17 700 LSMH B/C Canada (Rogers), USA (AT&T) Antigua & Barbuda (Digicel), Bahamas (BTC), Cayman Islands (C&W LIME) No No No No
18 800 No No No Japan (au)
(to be replaced by band 26)
No No
19 800 No No No Japan (NTT Docomo)
(to be replaced by band 26)
No No
20 800 EUDD No No Yes Qatar (Ooredoo, Vodafone) Yes Fiji (Digicel)
21 1500 UPDC No No No Japan (NTT Docomo) No No
22 3500 No No (no deployments) No No No
23 2000 S-Band USA
(no deployments)
No No No No No
24 1600 L-Band USA
(no deployments)
No No No No No
25 1900 EPCS A-G USA (Sprint) (no deployments) No No No No
26 850 ECLR USA (Sprint) (no deployments) No (no deployments) No (no deployments)
27 800 SMR USA
(no deployments)
No No No No No
28 700 APT No (no deployments) (no deployments) Taiwan (FarEasTone, Taiwan Mobile, Ambit Microsystems Corp (planned), APT (planned)), Japan (NTT docomo, au, E MOBILE (planned)) (no deployments) Australia (Optus, Telstra), New Zealand (Vodafone, Spark), Papua New Guinea (Digicel)
29 700 LSMH D/E USA (AT&T)
(no deployments)
No No No No No
30 Reserved Reserved Reserved Reserved Reserved Reserved
31 Reserved Reserved Reserved Reserved Reserved Reserved
32 Reserved Reserved Reserved Reserved Reserved Reserved
33 TDD 2100 IMT No No (no deployments) Sri Lanka, Singapore, Malaysia
(no deployments)
No Australia
(no deployments)
34 TDD 2100 IMT No No (no deployments) China, Japan
(no deployments)
No No
35 TDD 1900 PCS (no deployments) (no deployments) No No No No
36 TDD 1900 PCS (no deployments) (no deployments) No No No No
37 TDD 1900 PCS (no deployments) (no deployments) No No No No
38 TDD 2600 IMT-E No Brazil (On Telecom, SKY Brasil) Poland (Aero2), Russia (MegaFon, MTS), Spain (COTA), Sweden (3) Saudi Arabia (Mobily, Zain) Uganda (MTN) No
39 TDD 1900 No No No China (China Mobile) (in Trial) No No
40 TDD 2300 No (no deployments) Russia (Vainah Telecom) Yes Yes Australia (NBN Co, Optus), Vanuatu (WanTok)
41 TDD 2500 BRS/EBS USA (Sprint, nTelos (in Trial)) No No China (China Mobile, China Telecom, China Unicom), Japan (SoftBank (WCP)) No No
42 TDD 3500 Canada (ABC Communications) Chile (Entel) (in Trial) Belgium (b-lite), United Kingdom (UK Broadband) Bahrain (Menatelecom) No No
43 TDD 3700 No No United Kingdom (UK Broadband) No No No
44 TDD 700 APT No No No China (in Trial) No No

Technology demos[edit]

  • In September 2007, NTT Docomo demonstrated e-UTRA data rates of 200 Mbit/s with power consumption below 100 mW during the test.[22]
  • In April 2008, LG and Nortel demonstrated e-UTRA data rates of 50 Mbit/s while travelling at 110 km/h.[23]
  • February 15, 2008 - Skyworks Solutions has released a front-end module for e-UTRAN.[24][25][26]

See also[edit]

References[edit]

  1. ^ a b 3GPP UMTS Long Term Evolution page
  2. ^ a b c 3GPP TS 36.306 E-UTRA User Equipment radio access capabilities
  3. ^ a b 3GPP TS 36.300 E-UTRA Overall description
  4. ^ 3GPP TS 36.201 E-UTRA: LTE physical layer; General description
  5. ^ 3GPP TS 36.321 E-UTRA: Access Control (MAC) protocol specification
  6. ^ 3GPP TS 36.322 E-UTRA: Radio Link Control (RLC) protocol specification
  7. ^ 3GPP TS 36.323 E-UTRA: Packet Data Convergence Protocol (PDCP) specification
  8. ^ 3GPP TS 36.331 E-UTRA: Radio Resource Control (RRC) protocol specification
  9. ^ 3GPP TS 24.301 Non-Access-Stratum (NAS) protocol for Evolved Packet System (EPS); Stage 3
  10. ^ http://cp.literature.agilent.com/litweb/pdf/5989-7898EN.pdf
  11. ^ TS 36.211 rel.11, LTE, Evolved Universal Terrestrial Radio Access, Physical channels and modulation - chapters 5.2.3 and 6.2.3: Resource blocks etsi.org, january 2014
  12. ^ LTE Frame Structure and Resource Block Architecture Teletopix.org, retrieved in august 2014.
  13. ^ 3GPP TS 36.212 E-UTRA Multiplexing and channel coding
  14. ^ 3GPP TS 36.211 E-UTRA Physical channels and modulation
  15. ^ Nomor Research Newsletter: LTE Random Access Channel
  16. ^ 3GPP LTE / LTE-A Standardization: Status and Overview of Technologie, slide 16
  17. ^ 4G speed record smashed with 1.4 Gigabits-per-second mobile call #MWC12
  18. ^ 3GPP TS 36.101 E-UTRA: User Equipment (UE) radio transmission and reception
  19. ^ 3GPP LTE Standards Update
  20. ^ "Vodafone CR sets out stall to blanket over 50% of country with 3G/LTE by 1Q14". TeleGeography. 2013-11-06. Retrieved 2013-12-12. 
  21. ^ "Vodafone’s Czech unit extends LTE-900 coverage". TeleGeography. 2013-12-12. Retrieved 2013-12-12. 
  22. ^ NTT DoCoMo develops low power chip for 3G LTE handsets
  23. ^ Nortel and LG Electronics Demo LTE at CTIA and with High Vehicle Speeds :: Wireless-Watch Community at the Wayback Machine (archived June 6, 2008)
  24. ^ "Skyworks Rolls Out Front-End Module for 3.9G Wireless Applications. (Skyworks Solutions Inc.)" (free registration required). Wireless News. February 14, 2008. Retrieved 2008-09-14. 
  25. ^ "Wireless News Briefs - February 15, 2008". WirelessWeek. February 15, 2008. Retrieved 2008-09-14. 
  26. ^ "Skyworks Introduces Industry's First Front-End Module for 3.9G Wireless Applications.". Skyworks press release (Free with registration). 11 Feb 2008. Retrieved 2008-09-14. 

External links[edit]