LTE Frequency Bands, Spectrum & Channels

There are many frequency bands allocated to accommodate available spectrum in different countries for LTE (FDD & TDD) which are numbered and have defined limits. Radio channel numbers are also allocated.

4G LTE includes:
What is LTE LTE OFDMA / SCFDMA MIMO LTE Duplex LTE frame & subframe LTE data channels LTE frequency bands LTE EARFCN UE categories / classes LTE-M (Machine to Machine) LTE-LAA / LTE-U VoLTE SRVCC

LTE Advanced topics: LTE Advanced introduction Carrier aggregation Coordinated multipoint LTE relay Device to device, D2D

There are very many different LTE frequency bands which have been allocated around the globe.

As different countries have different areas of available spectrum it has not been possible to have a high level of coordination from one country to the next and this has issues with roaming and the number of bans needed for handsets.

Each frequency band is allocated a number so it can be defined easily and its limits known.

The LTE radio channels are also allocated numbers - these can be calculated from a simple defined formula. By having defined radio channels, they can be coordinated globally to facilitate roaming.

LTE bands for FDD & TDD

The spectrum requirements and hence the frequency band allocations for LTE are different for FDD and TDD.

FDD LTE bands: FDD spectrum requires pair bands, one of the uplink and one for the downlink. It is also important that there is sufficient spacing between the top of the lower band and the bottom of the upper band to allow sufficient filtering. Also the uplink to downlink channel spacing must be sufficient to allow sufficient filtering to prevent the transmitted signal from entering he receiver and desensitising it.
TDD LTE bands : TDD transmissions only require a single band and in this way paired spectrum is not needed.

The different LTE frequency allocations or LTE frequency bands are allocated numbers. Currently the LTE bands between 1 & 22 are for paired spectrum, i.e. FDD, and LTE bands between 33 & 41 are for unpaired spectrum, i.e. TDD.

FDD LTE frequency band allocations

There is a large number of allocations or radio spectrum that has been reserved for FDD, frequency division duplex, LTE use.

Definitions of parameters used in defining the LTE bands. — LTE frequency band definitions

The FDD LTE frequency bands are paired to allow simultaneous transmission on two frequencies. The bands also have a sufficient separation to enable the transmitted signals not to unduly impair the receiver performance. If the signals are too close then the receiver may be "blocked" and the sensitivity impaired. The separation must be sufficient to enable the roll-off of the antenna filtering to give sufficient attenuation of the transmitted signal within the receive band.

FDD LTE Bands & Frequencies
LTE Band Number	Uplink (MHz)	Downlink (MHz)	Width of Band (MHz)	Duplex Spacing (MHz)	Band Gap (MHz)
1	1920 - 1980	2110 - 2170	60	190	130
2	1850 - 1910	1930 - 1990	60	80	20
3	1710 - 1785	1805 -1880	75	95	20
4	1710 - 1755	2110 - 2155	45	400	355
5	824 - 849	869 - 894	25	45	20
6	830 - 840	875 - 885	10	35	25
7	2500 - 2570	2620 - 2690	70	120	50
8	880 - 915	925 - 960	35	45	10
9	1749.9 - 1784.9	1844.9 - 1879.9	35	95	60
10	1710 - 1770	2110 - 2170	60	400	340
11	1427.9 - 1452.9	1475.9 - 1500.9	20	48	28
12	698 - 716	728 - 746	18	30	12
13	777 - 787	746 - 756	10	-31	41
14	788 - 798	758 - 768	10	-30	40
15	1900 - 1920	2600 - 2620	20	700	680
16	2010 - 2025	2585 - 2600	15	575	560
17	704 - 716	734 - 746	12	30	18
18	815 - 830	860 - 875	15	45	30
19	830 - 845	875 - 890	15	45	30
20	832 - 862	791 - 821	30	-41	71
21	1447.9 - 1462.9	1495.5 - 1510.9	15	48	33
22	3410 - 3500	3510 - 3600	90	100	10
23	2000 - 2020	2180 - 2200	20	180	160
24	1625.5 - 1660.5	1525 - 1559	34	-101.5	135.5
25	1850 - 1915	1930 - 1995	65	80	15
26	814 - 849	859 - 894	30 / 40		10
27	807 - 824	852 - 869	17	45	28
28	703 - 748	758 - 803	45	55	10
29	n/a	717 - 728	11
30	2305 - 2315	2350 - 2360	10	45	35
31	452.5 - 457.5	462.5 - 467.5	5	10	5
32	DL CA Only	1452 - 1496	44	N/A	N/A
65	1920 - 2100	2120 - 2200	90	190	20
66	1710 - 1780	2110 - 2200	90	400	330
67	DL CA Only	738 - 758	20	N/A	N/A
68	698 - 728	753 - 783	30	55	25
69	DL CA Only	2570 - 2620	50	N/A	N/A
70	1695 - 1710	1995 - 2020	25	295	285
71	663 - 698	617 - 652	35	-46	11
252	DL CA Only	5150 - 5250	100	N/A	N/A
255	DL CA Only	5725 - 5850	125	N/A	N/A

Notes:
bands 15 and 16 are now obsolete
DL CA Only refers to bands that are used for downlink carrier aggregation only
Bands 252 and 255 use the unlicensed spectrum and used with LTE-LAA / LTE-U.

. . . . Additional . . . . LTE frequency bands information.

TDD LTE frequency band allocations

With the interest in TDD LTE, there are several unpaired frequency allocations that are being prepared for LTR TDD use. The TDD LTE bands are unpaired because the uplink and downlink share the same frequency, being time multiplexed.

TDD LTE Bands & Frequencies
LTE Band Number	Allocation (MHz)	Width of Band (MHz)
33	1900 - 1920	20
34	2010 - 2025	15
35	1850 - 1910	60
36	1930 - 1990	60
37	1910 - 1930	20
38	2570 - 2620	50
39	1880 - 1920	40
40	2300 - 2400	100
41	2496 - 2690	194
42	3400 - 3600	200
43	3600 - 3800	200
44	703 - 803	100
45	1447 - 1467	20
46	5150 - 5925	775
47	5855 - 5925	70

There are regular additions to the LTE frequency bands / LTE spectrum allocations as a result of negotiations at the ITU regulatory meetings. These LTE allocations are resulting in part from the digital dividend, and also from the pressure caused by the ever growing need for mobile communications. Many of the new LTE spectrum allocations are relatively small, often 10 - 20MHz in bandwidth, and this is a cause for concern. With LTE-Advanced needing bandwidths of 100 MHz, channel aggregation over a wide set of frequencies many be needed, and this has been recognised as a significant technological problem. . . . . . . . .

. . . . Additional . . . . LTE frequency bands information.

LTE radio channel bandwidths

LTE supports different channel bandwidths and as a result a different number of resource blocks can be supported.

For all the channel bandwidths except 1.4 MHz, the resource blocks in the transmission bandwidth fill up 90% of the channel bandwidth.

Radio Channel Bandwidths Specified in LTE
Channel Bandwidth	Number of Resource Blocks
1.4 MHz	6
3 MHz	15
5 MHz	25
10 MHz	50
15 MHz	75
20 MHz	100

The LTE bands have proliferated around the globe. This has resulted from the very fragmented amounts of spectrum that have been available. This has made the design of handsets for roaming more difficult as filters need to ensure that out of band products are sufficiently reduced, but having banks of filters to accommodate the huge variety of bands is difficult.