A Fully Integrated MIMO Multiband Direct ... - Semantic Scholar
A Fully Integrated MIMO Multiband Direct Conversion CMOS Transceiver for WLAN Applications (802.11n) Arya Behzad et al. (Broadcom Corporation) Reviewed by Yu-Shan Wang IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 42, NO. 12, DECEMBER 2007
Outline • Introduction of 802.11n and MIMO • Transceiver architecture - TX,RX,PLL • Calibration techniques - LOFT, IQ mismatch • Measurement Summary • Conclusion
Comparison of WLAN standards 802.11a
802.11b
802.11g
802.11n
5G
2.4G
2.4G
2.4G/5G
Data rate(bps) 6-54M
5.5-11M
1-54M
>100M
Modulation
CCK
DSSS/CCK/O FDM
OFDM
Freq. band(Hz)
OFDM
• IEEE 802.11n highlights: – Spatial division multiplexing (SDM) through the use of MIMO–OFDM – Transmit beam forming – Bandwidth expansion (40MHz) – Advanced backend processing
Why MIMO?
• Spatial multiplexing can increase the channel capacity dramatically • CSISO = BW log2(1 + SNR) • CMIMO = min(n, m) BW log2(1 + SNR)
Transceiver
Receiver architecture
•Fully differential Direct conversion receiver •HPVGA programmable gain of 0 to 30dB in 3dB steps •4th order Butterworth LPF bandwidth 5,10,20MHz • RX gain >100dB •RX IIP3 of -12dBm @ high gain •RX NF of 4dB @ maximum gain
Transmitter
•Direct conversion •Driving 50 ohm load through a balun and internally matched to 100 ohm differential •LOFT and IQ calibration •OIP3 of +14dBm in the A-band while OIP3 of +16dBm in the G-band •EVM 270Mbps • Effective throughput >190Mbps • Can utilized in a multi-transceiver configuration to build a larger MIMO system (4X4)
Questions?
Thank you
Outline • Introduction of 802.11n and MIMO • Transceiver architecture - TX,RX,PLL • Calibration techniques - LOFT, IQ mismatch • Measurement Summary • Conclusion
Comparison of WLAN standards 802.11a
802.11b
802.11g
802.11n
5G
2.4G
2.4G
2.4G/5G
Data rate(bps) 6-54M
5.5-11M
1-54M
>100M
Modulation
CCK
DSSS/CCK/O FDM
OFDM
Freq. band(Hz)
OFDM
• IEEE 802.11n highlights: – Spatial division multiplexing (SDM) through the use of MIMO–OFDM – Transmit beam forming – Bandwidth expansion (40MHz) – Advanced backend processing
Why MIMO?
• Spatial multiplexing can increase the channel capacity dramatically • CSISO = BW log2(1 + SNR) • CMIMO = min(n, m) BW log2(1 + SNR)
Transceiver
Receiver architecture
•Fully differential Direct conversion receiver •HPVGA programmable gain of 0 to 30dB in 3dB steps •4th order Butterworth LPF bandwidth 5,10,20MHz • RX gain >100dB •RX IIP3 of -12dBm @ high gain •RX NF of 4dB @ maximum gain
Transmitter
•Direct conversion •Driving 50 ohm load through a balun and internally matched to 100 ohm differential •LOFT and IQ calibration •OIP3 of +14dBm in the A-band while OIP3 of +16dBm in the G-band •EVM 270Mbps • Effective throughput >190Mbps • Can utilized in a multi-transceiver configuration to build a larger MIMO system (4X4)
Questions?
Thank you
