Question

In telecommunication, Long-Term Evolution (LTE) is a standard for wireless broadband communication for mobile devices and data terminals. In this communication technology, a resource block as the smallest unit of bandwidth resource is allocated to a user. Explain the specification of a resource block and calculate how many bits are delivered by a resource block where all the subscribers are modulated by with 64 QAM.

Answer 1

In Telecommunication and networking, The terms LTE refers to a standard for wireless broadband communications. It is developed by 3GPP ( 3rd Generation Partnership project)

SPECIFICATION:

A Resource block is a smallest unit of bandwidth allocated to the user and a resource block is made up of even smaller elements called as resource elements. A resource element is the smallest modulation structure in LTE which means it is the smallest unit that can be modulated to send and receive information in bits. A resource element is 15KHZ subcarrier by one symbol.

Generally in LTE, the scheme OFDMA is used which is a multi-carrier scheme that allocates resources to users. OFDMA uses OFDM that is Orthogonal Frequency Division Multiplexing and modulates each subcarrier using the QPSK, 16-QAM or 64 QAM modulation formats.

ANSWER:

If we use OFDMA with 64 QAM modulation format on a resource block than the number of bits delivered will be:

• One resource block = 12 * 7 = 84 resource element.
• 64 QAM = 6 bits.
• Since a resource element can deliver 6 bits using 64 QAM
• Then a resource block can deliver 84 * 6 = 504 bits.