1. Digital Transceiver Implementation
Characterization Presentation
Barak Shaashua Barak Straussman
Supervisor: Idan Shmuel

2. Project Goals Implementation of transceiver with Labview on FPGA.
Project parts:
16 QAM Tranceiver
8 PSK Tranceiver

3. Constellation Mapping
Transmitter Block Diagram I
Source Coder
Channel Coder
 Serial /
Parallel 
Constellation Mapping Q
DAC
LPF I
כמה אפשרויות: DAC לפני ה – combine, או אחרי...
+ π/2
ISI
Filter
Up Converter
Combiner Q
Sin(wt)
DAC
LPF

4. Receiver Block-Diagram
LPF I
+ π/2
Timing & Carrier Recovery RF
ADC
Sin(wt) Q
LPF I
Channel Decoder
Symbol Decision
Constellation
Mapping
Parallel / Serial Q
(+ Source)

5. Project Environment Software LabView 2010 v.10 (FPGA, RF toolbox)
Tabor – ArbConnection
Hardware
FPGA – Virtex5, NI FlexRio Board
NI 5761 Digitizer
Tabor – wx2182
Scope, Spectrum Analyzer
Combiner – 5M – 2500M
NI 5761 Digitizer – 14-Bit, 250 MS/s, 500Mhz BW
Tabor – wx2182, 2.1GS/s, 16Mb waveform memory, 1Ghz (sin) , 12 digits resolution.

6. Hardware Connection

7. Rates FPGA – 400Mb/s Tabor – 2.1GS/s, 16MB waveform memory
Digitizer – 250MS/s
GPIB – 1.5MB/s
LAN – Fast Ethernet 100Mb/s
Coaxial cable – BW 4.2Ghz
Our IF frequency: 100Mhz
Tabor Symbol Rate possible: 100Khz – 500Mhz

8. Time Table
1.2 – 28.2
8.1 – 31.1
25.12 – 7.1
4.12 – 24.12
27.11– 3.12
3.11 – 26.11
Studying project material & work environment
Transmitter Block Design
Receiver Block Design
FPGA Simulation & debugging
Tests

9. Channel Coder Block Code – as Hamming Code:
Implementation with vectors and matrices representation
Able to detect up to 2 errors and correct one

10. ISI Symbol interference results of dispersion in transmission medium
ISI filter decreases this interference
Filter: Root Raised Cosine

11. Constellation Mapping
Implementation with Lock Up Table
Symbols - according to Gray Code
One LUT for 16QAM, another for PSK

12. Timing & Carrier Recovery
Recovers 3 elements:
Symbol Timing – Grander Algorithm
Carrier Frequency
Carrier Phase
Makes use of Digital PLL

13. Symbol Decision Noise Sources: Channel, Quantization, Aliasing…
Assumptions:
Noise is AWGN, orthogonal & i.i.d
Uniform symbol probability
Symbols decision according to Euclidian distance only.
רעש יכול לנבוע למשל מה-ADC – רעש קוונטיזציה, רעש מקיפולים..