Questions tagged [lte]
The lte tag has no usage guidance.
1
vote
1answer
23 views
Quantized error in scatter plots for a hamming windowed LTE signal
I have a time domain signal based on LTE standards.
Carrier spacing = 15KHz, Symbols per slot = 6, extended Cyclic Prefix = 512 samples
FFT size = 2048, No. of sub carriers = 1200, channel BW = 20MHz, ...
0
votes
0answers
30 views
How to do carrier aggregation?
I have generated 20 MHz bandwidth LTE waveform. I wanted to do carrier aggregation of this signal to get 100 MHz Signal.
I want to understand how carrier aggregation is done mathematically, so using ...
1
vote
1answer
97 views
am I recording LTE uplink signals?
I have this app in my phone which tells me the LTE UL frequency and power:
so I went with my SDR and measured the received signal at that frequency:
Now, how can I be sure this is the transmitted ...
0
votes
1answer
450 views
What is the difference between Antenna port and Physical Antenna in LTE?
I have just started working on the 5G NR physical layer and I have difficulty understanding the concept of Antenna Port at the downlink.
In release 10 there supposedly 15-22 antenna ports for CSIRS (...
0
votes
0answers
82 views
Wrap Around Viterbi Algorithm for tail biting decoding “WAVA”
Tail-biting where the initial and final states of the encoder are identical.
Tail biting is done by initializing the shift register contents with the last m
information bits in the input block to ...
-1
votes
2answers
90 views
What is the transmission frequency of mimo antennas?
I was wondering what is the operating frequency of different antenna's in a MIMO system? Do they work in the same band or separate band that the LTE(22 bands) assigned with?
Thank you.
2
votes
2answers
677 views
Why is LTE either FDD or TDD?
In LTE systems, up- and downlink are duplexed either using FDD or TDD. Why has this not been designed to utilize the same multiplexing technique as used for the downlink (OFDMA)? Resource blocks could ...
1
vote
1answer
205 views
SC-FDMA in LTE system
I am trying to understand how SC-FDMA is used in LTE system. Every description I found so far refers to DFT and IDFT.
However, when I checked 3GPP TS 36.211 chapter 5.4 (SC-FDMA baseband signal ...
0
votes
1answer
65 views
Why OFDM is more appropriate with MIMO than other multiple access method?
As read from MIMO-OFDM wikipidia page says
Research conducted during the mid-1990s showed that while MIMO can be used with other popular air interfaces such as time-division multiple access (TDMA) ...
4
votes
1answer
3k views
The necessity of null subcarrier in OFDM?
In looking to LTE specifications, with the subcarrier spacing $\Delta f = 15 \textrm{kHz}$,
for bandwidth $10 \textrm{MHz}$, fft size $N_{fft} = 1024$ that needs a sampling rate $F_s \geq 1024 \times ...
2
votes
2answers
2k views
System Frame Number in LTE Specifications
What exactly is System Frame Number in LTE specifications? What is the use of it?
I have read that it is a 10 bit number and used for synchronization purposes. But it's not clear how it helps for ...
1
vote
1answer
510 views
SC-FDMA disadvantages
I understand the advantages of SC-FDMA over OFDM and I also understand the disadvantage of additional complexity (FFT block), are there another disadvantages?
Also, if $N$ has to be bigger than $M$ ($...
0
votes
0answers
756 views
Difference between single layer and dual layer beamforming in LTE
I'm trying to understand the difference between single and dual layer beamforming in LTE as described in TS 36.101 section B.4.1 and B.4.2 respectively. Also refer to TS 36.211 section 6.3.4.2.3 for ...
1
vote
0answers
109 views
How often do a LTE eNodeB scheduler schedule?
Scheduler schedules the resource for each UE. How often do a LTE eNodeB scheduler schedule? Is the time between each scheduling fixed?
any idea/reference will be great help on this regard. Thanks.