How is transport block size determined?

How is transport block size determined?

Step to Calculated TBS The total number of REs within the bandwidth of a single RB is 12 x 14 = 168 using normal cyclic prefix. The final value is multiplied by the number of allocated Resource Blocks to generate a value for .

What is transport block size in LTE?

TB Size(transport block size) defines how many bits MAC layer transfers to Physical layer per TTI (Transmission Time Interval, defined as 1ms). Note: TM1/TM2 can carry 1 TB Size per TTI, TM3/TM4 can carry 2 TB Size per TTI (two code word).

How is TB LTE size calculated?

Example: Given that MCS is 14 and NPRB is 3, determine transport block size(TBS). MCS of 14 gives ITBS equal to 13 from table 7.1. 7.1-1 as mentioned in 3GPP 36.213 document. Now ITBS of 13 and NPRB of 3 gives TBS of 744 bits from 7.1.

What is transport block?

Transport Block is a packet of data which is passed between the MAC and Physical layers. It is passed downwards at the transmitter and upwards at the receiver. A Transport Block undergoes Physical layer processing at the transmitter before being mapped onto the PDSCH for transfer across the air-interface.

How Throughput is calculated in LTE?

If modulation used is 64 QAM (6 bits per symbol) then throughput will be 16.8×6=100.8Mbps for a single antenna port. If we consider a 2×2 MIMO system then this throughput will be double i.e. 100.8×2= 201.6 Mbps and with 4×4 MIMO system then throughput is about 100.8×4= 403.2 Mbps.

What is code block in 5G?

In fifth generation (5G) new radio (NR), the medium access control (MAC) layer organizes the data into the transport block and transmits it to the physical layer. The transport block consists of up to million bits. The code block consists of up to 8448 bits.

How is LTE code rate calculated?

The calculation of LTE code rate is done based on MCS, PRBs and OFDM symbols per slot. The LTE code rate calculator outputs code rate. It takes into account percent of REs used in control channel operation. The PRBs stands for Physical Resource Blocks allocated to the UE by eNB.

What is the largest possible transport block?

In 5G NR, the maximum transport block size is 1,277,992 [6]. The processing of the transport block is shown in Figure 1 [7]. If the transport block size is larger than 3824, a 16-bit CRC is added at the end of the transport block. Otherwise, a 24-bit CRC is added at the end of the transport block.

What is the formula to calculate throughput?

What Is the Throughput Formula? The throughput efficiency formula can be calculated more than one way, but the general formula is I = R * T. In other words, Inventory = Rate multiplied by Time, where “rate” is the throughput.

How is maximum throughput calculated?

Network throughput refers to the average data rate of successful data or message delivery over a specific communications link. Network throughput is measured in bits per second (bps). Maximum network throughput equals the TCP window size divided by the round-trip time of communications data packets.

How is resource block calculated in 5G?

In 5G, One NR Resource Block (RB) contains 12 sub-carriers in frequency domain similar to LTE. In LTE resource block bandwidth is fixed to 180 KHz but in NR it is not fixed and depend on sub-carrier spacing.

How is transport block size calculated in LTE?

Since the size of transport block is not fixed, often a question comes to mind as to how transport block size is calculated in LTE. If we only consider “Uplink direction” and we assume that the UE is already attached to the network, then data is first received by PDCP (Packet data compression protocol) layer.

How to calculate the downlink transport block size?

Throughput is simply = Transport block size*(1000) = 776 *1000 = 776000 bits / seconds = 0.77 mbps (Assuming MIMO not used) Please check this Throughput Calculatorwhich takes MCS values and number of resource blocks as input to calculate the downlink throughput

How does RLC change the transport block size?

RLC layer will concatenate or segment the data coming from PDCP layer into correct block size and forward it to the MAC layer with its own header. Now MAC layer selects the modulation and coding scheme configures the physical layer. The data is now in the shape of transport block size and needed to be transmitted in 1ms subframe.

How is the code rate of a transport block defined?

Code Rate. In simple words, code rate can be defined as how effectively data can be transmitted in 1ms transport block or in other words, it is the ratio of actual amount of bits transmitted to the maximum amount of bits that could be transmitted in one transport block. code rate = (TBS + CRC) / (RE x Bits per RE) where.

Theoretically speaking, data throughput is TB Size/TTI(1ms) for TM1/TM2, 2*TB Size/TTI for TM3/TM4. To get maximum rate, we need choose maximum TB Size. TB Size is affected by bandwidth, modulation and allocated RB, and we can figure out maximum TB Size on CS8 IT GUI.

What is codeword in 5G?

The output of a coding chain is a codeword. 5G supports transmission of up to 8 layers to a single user on the downlink. This means that there can be up to eight streams transmitted in parallel. The coded data is then mapped to the physical downlink shared channel or PDSCH.

What is code rate in 5G?

5G NR supports QPSK, 16 QAM, 64 QAM and 256 QAM modulation . With QPSK there are 2 bits can be transmitted per RE, with 16QAM it can be 4 bits, with 64QAM it can be 6 bits and with 256QAM it can 8 bits. Code rate can be defined as the ratio between useful bit and total transmitted bit (Useful + Redundant Bits).

What is CRC in 5G?

In fifth generation (5G) new radio (NR), the medium access control (MAC) layer organizes the data into the transport block and transmits it to the physical layer. The transport block consists of up to million bits. Both the transport block and the code block have a cyclic redundancy check (CRC) attached.

What is layer mapping in 5G?

(2) Layer Mapping : This is the process where each codeword is mapped to mapped to one or multiple layers. Refer to Layer Mapping page. (3) Precoding : This is process where the layer data are allocated to multiple antenna ports (logical antenna ports in this stage).

What is Pdsch in 5G?

PDSCH (Physical Downlink Shared Channel) is the data-bearing channel in 5G-NR. For acquiring the channel quality, NR specifies a special type of cell-specific reference signal which can be configured for transmission on up-to 32 antenna ports. The CSI-RS resources are code, frequency and time division multiplexed.

How is transport block size determined according to ts36.213?

NOTE 1 : Transport Block Size is determined by the number of RB and MCS according to TS36.213 Table 7.1.7.1-1 and Table 7.1.7.1-2 NOTE 2 : Number of the scheduled subframe mean that the subframe that is scheduled to transmit data. if UE is in max throughput condition, you may assume that every subframe is scheduled to transmit

How big is a transport block in ENB?

We have to refer to the Table 7.1.7.1-1 and Table 7.1.7.2.1-1 from 3GPP 36.213 Lets assume that eNB assigns MCS index 20 and 2 resource blocks (RBs) on the basis of CQI and other information for downlink transmission on PDSCH. Now the value of TBS index is 18 as seen in Table 7.1.7.1-1

How does Mac decide on transport block size?

From this step the MAC can decide upon the modulation and coding scheme index ( I_MCS ) and then decide upon the number of resource blocks ( N_PRB ), that can be allocated to the user.