Tag : bandwidth

Spreading Technology in WCDMA

Spreading Technology in WCDMA

Spreading consists of 2 steps: Channelization operation, which transforms data symbols into chips Scrambling operation is applied to the spreading signal Spreading means increasing the bandwidth of the signal beyond the bandwidth normally required
OFDMA Parameter for LTE

OFDMA Parameter for LTE

How Many OFDMA Parameter for LTE? Which is OFDMA Parameter for LTE ? The width of a Sub-carrier is 15 kHz whatever the bandwidth The bandwidths are: 1.4, 3, 5, 10, 15 and 20
OFDMA Transmitter in LTE

OFDMA Transmitter in LTE

How OFDMA Transmitter in LTE ? In the downlink, OFDM is selected to efficiently meet E-UTRA performance requirements. With OFDM,  it is straightforward to exploit frequency selectivity of the multi-path channel with lowcomplexity receivers. 
UL Allocation (SC-FDMA) in LTE

UL Allocation (SC-FDMA) in LTE

SC-FDMA utilizes single carrier modulation, DFT-spread orthogonal frequency multiplexing, and frequency domain equalization. LTE uses OFDMA on the DL. It allocates DL bandwidth to the user based on resource blocks, rather than individual subcarriers.
3G LTE Requirements

3G LTE Requirements

Spectrum efficiency  DL : 3-4 times UL : 2-3 times Frequency Spectrum Scalable bandwidth : 1.4, 3, 5, 10, 15, 20MHz To cover all frequencies of IMT-2000: 450 MHz to 2.6 GHz Peak data
Advance Future for Mobile WiMAX

Advance Future for Mobile WiMAX

Orthogonal frequency division multiple access (OFDMA): Mobile WiMAX uses OFDM as a multiple-access technique, whereby different users can be allocated different subsets of the OFDM tones. As discussed in detail in Chapter 6, OFDMA
Pulse shaping and spectrum in LTE

Pulse shaping and spectrum in LTE

RF engineering is a trade off between: required radio spectrum (bandwidth), speed of data transmission (bit rates) and complexity of implementation. The pulse form used to modulate complex data symbols to the radio carrier