LTE Sub-carrier How Many Sub Carrier in LTE? Read below,..There are different kinds of sub-carriers: Data sub-carrier Pilot Sub-carrier DC sub-carrier Guard Sub-carrier The result is intersymbol interference not only within a subcarrier but also between subcarriers. To prevent symbols from overlapping and to reduce the intersymbol. DC stands for Direct Current and it is … Read more
In FDM, the sub-carriers are separated in the frequency domain to avoid interference between the sub-channels It results in a loss of spectrum efficiency because the frequency guard band can not be used to send data.The OFDM allows one to remove the frequency guard band. Benefit: There are more sub-carriers, so more symbols are … Read more
OFDMA Principles in LTE Orthogonal Frequency Division Multiple Access (OFDMA) is a key technology used in Long-Term Evolution (LTE) to efficiently manage the transmission of data over the radio interface. Here’s an explanation of OFDMA principles in LTE: Frequency Division Multiplexing (FDM): OFDMA uses FDM to divide the available frequency spectrum into multiple subcarriers. Each … Read more
Constellation in LTE In LTE (Long-Term Evolution), the term “constellation” typically refers to the modulation scheme used for transmitting data over the air interface. LTE uses Quadrature Amplitude Modulation (QAM) to encode multiple bits into a single symbol. The constellation diagram visually represents how the amplitude and phase of the modulated signals correspond to specific … Read more
The 3G LTE uses 3 Quadrature Amplitude Modulations (QAMs) depending on the radio quality. QAM uses both the amplitude and the phase. LTE devices use QPSK, 16QAM and 64QAM to modulate data and control information. The eNodeB supports all of these modulation techniques for the downlink direction. However, 64QAM is optional in the uplink direction. … Read more
All MS transmit on same frequency but with different PN codes to create different logical channels. Some channels marked for Access are used for signaling and control. While Walsh Codes identifies different channels, PN codes are used to identify Cells (by 15 bit code) and MS’s (by 42 bit codes). As each MS receives a … Read more
LTE Architecture The LTE (Long-Term Evolution) architecture consists of several key components: User Equipment (UE): Mobile devices like smartphones or tablets used by end-users. Evolved NodeB (eNB): Base station responsible for radio communication with the UE. It includes the radio transceiver and performs functions like encryption and modulation. Mobility Management Entity (MME): Manages UE mobility, … Read more
In any two-way radio system, the radio pathlosses and the equipment output powers and sensitivities must be taken into account for both directions. This is especially true in a mobile network (e.g. downlink: BS to UE and uplink: UE to BS), where there are different characteristics for the uplink and downlink paths. These include, for … Read more
The system designer will need to determine the specific RF link budget parameters to be used when designing the system. The following figure shows the typical gains and losses that are encountered in the RF path. An RF link budget must be determined for each sector of each site. The RF link budget for each … Read more
Transmit Diversity Gain in LTE In Long-Term Evolution (LTE) wireless communication systems, transmit diversity gain plays a crucial role in enhancing the reliability and performance of data transmission. Transmit diversity involves the use of multiple antennas at the transmitter to improve the quality of the received signal at the receiver. One common technique employed in … Read more