In INDIA, the 4 G LTE band-40 range of 2300 to 2400 MHz (TD-LTE) is effective (online) and provided by operators in the Indian Territory. India’s Government also auctions the other LTE band with a frequency of 1800 MHz (FDD-LTE). But no telecommunications operators give this LTE band. This 100MHz bandwidth of Band-40 seems to be from 2300MHz to 2400MHz but is shared between downlink and uplink transmissions. Downlink relates to transmissions from eNB(i.e., base station) to UE(i.e., mobile user), and uplink pertains to transmissions from UE to eNB.
There are two topologies in LTE technology: LTE FDD and LTE TDD (or TD-LTE). FDD is a Frequency division duplex, and TDD is a time division duplex. In TDD, one frequency is used at various times, both by uplink and downlink. In FDD, two distinct frequencies are assigned to uplink and downlink. Simultaneous transmissions in both uplink and downlink can, therefore, exist in FDD.
Indian telecom operator offers 4G LTE service.
The major telecommunications operators are leading providers of 4g LTE bands in India. Airtel, Aircel, Reliance Jio Infocom Ltd, and Vodafone are telecom operators. Airtel is the first company to have introduced the LTE service in INDIA. Airtel uses the 2300 MHz TD-LTE band to provide the service. Aircel is the second to provide LTE service in the same 2300MHz TD-LTE band. Reliance Jio Infocom Ltd will launch 4 G LTE services in TD-LTE(2300MHz) and FD-LTE(1800MHz) frequency bands. Vodafone also provides Vodafone LTE bands in India in the FDD-LTE frequency band(1800MHz).
The LTE standard backs different frequency bands for different frequency allocations in other parts of the world. Before buying 4 G LTE phones in INDIA, one has to know which LTE frequency bands are accessible in INDIA and backed by Indian telecommunications operators. Currently, only the TD-LTE 2300 band is online. One needs to purchase an LTE phone that supports this band. There are LTE phones that facilitate both of these frequencies. So, if you buy these mobile devices, they will help the current TD-LTE band and FDD-LTE once accessible.
As the first mover, Bharti Airtel’s finest telecommunications operator began offering 4 G LTE services for customers back in 2012. After a slow start, Airtel is now aggressively pushing its 4 G services. At the end of 2015, Vodafone India and Idea Cellular began offering their 4 G LTE service in selected Indian cities. Jio’s commercial launch has disturbed the Indian telecommunications sector.
The LTE bands used in India are divided into separate LTE frequency bands. If you hope to move to a 4 G network, you must find suitable 4 G LTE-compatible devices. Indian telecommunications operators have been granted a spectrum license to operate 4 G LTE networks over BAND 5 LTE FDD (850 Mhz), BAND 3 LTE FDD (1800 Mhz), BAND 40 LTE TDD (2300 Mhz), and BAND 41 LTE TDD (2500 Mhz). Your best option is to get a mobile phone that claims to support BAND 40 or BAND 3, as most telcos operate under this BAND.
Due to negotiations at the ITU regulatory meetings, regular additions are made to the 4 G LTE frequency bands / LTE spectrum allocations. These LTE allocations are partly due to the digital dividend and the pressure created by the ever-increasing need for mobile communications. Several new LTE spectrum allocations seem to be relatively tiny, often 10-20MHz in bandwidth, which is a reason for concern.
With LTE-Advanced use of channel aggregation for 100 MHz bandwidths, channel aggregation over a wide range of frequencies is required; the availability of adequate spectrum has been recognized as a major technology problem.
The number of bands allocated to be used has expanded as the pressure on the spectrum rises. Due to different regulatory positions in various countries, it was not feasible for all LTE band allocations to be the same globally. Global allocations have not been feasible.
In some cases, the bands seem to overlap. Different countries have allocated frequencies differently now and traditionally because of the various levels of accessibility worldwide. LTE roaming might have had some constraints, as not all handsets or UEs will obtain the same frequencies.
FDD and TDD LTE frequency bands
FDD spectrum includes pair bands, one uplink, and one downlink band, while TDD necessitates a single band as the uplink and downlink would be at the same frequency but time apart. As a consequence, there are various LTE band allocations for both TDD and FDD. In some cases, these bands may coincide and, therefore, are feasible, even though it is doubtful that both TDD and FDD transmissions might be available on a particular LTE frequency band.
A single UE or smartphone device will often have to trace whether a TDD or FDD transmission must be created for a given band. The roaming UEs may experience both types in the same band. Therefore, they would have to detect how many types of transmission are being carried out on that particular LTE band at their current location. Many chipsets used in modern phones can perform with either FDD or TDD, generally within a specific frequency.
The number of bands assigned for use expanded as spectrum pressure also increased. Due to different regulatory positions in various countries, all LTE band allocations didn’t need to be the same worldwide. Global allocations have not been feasible. In some cases, the bands seem to overlap. It is because of the different levels of accessibility worldwide that various countries have assigned frequencies differently now and traditionally. This means that LTE roaming may have some restrictions, as not all handsets or UEs will view the same frequencies.
