Product Specs

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1. General Description
The Realtek RTL8821CE is a highly integrated single-chip that support 1-stream 802.11ac
solutions with Multi-user MIMO (Multiple-Input , Multiple-Output) STA mode with Wireless LAN
(WLAN) PCIExpress network interface controller with integrated Bluetooth 2.1/4.2 USB interface
controller. Itcombines a WLAN MAC, a 1T1R capable WLAN baseband, and RF in s single chip.
The RTL8821CE provides a complete solution for a high-performance integrated wireless and
Bluetooth device.
The RTL8821CE baseband implements Multi-user Multiple Input, Multiple Output (MU
MIMO)Orthogonal Frequency Division Multiplexing (OFDM) STA mode with one transmit and
one receive paths(1T1R). Features include one spatial stream transmissions, short Guard Interval
(GI) of 400ns, spatial spreading, and support for variant channel bandwidth. Moreover,
RTL8821CE provides one spatial stream space-time block code (STBC), Transmit Beamforming
(TxBF) and Low Density Parity Check (LDPC) to extend the range of transmission. As the
recipient, the RTL8821CE also supports explicit sounding packet feedback that helps senders with
beamforming capability.
For legacy compatibility, Direct Sequence Spread Spectrum (DSSS), Complementary Code
Keying (CCK)and OFDM baseband processing are included to support all IEEE 802.11b, 802.11g
and 802.11a data rates.Differential phase shift keying modulation schemes, DBPSK and DQPSK
with data scrambling capability are available, and CCK provides support for legacy data rates, with
long or short preamble. The high speed FFT/IFFT paths, combined with BPSK, QPSK, 16QAM,
64QAM and 256QAM modulation of the individual subcarriers, and rate compatible coding rate of
1/2, 2/3, 3/4, and 5/6, provide up to 433.3Mbps for IEEE 802.11ac MIMO OFDM.
The RTL8821CE builds in an enhanced signal detector, an adaptive frequency domain
equalizer, and a soft-decision Viterbi decoder to alleviate severe multi-path effects and mutual
interference in the reception of multiple streams. Robust interference detection and suppression are
provided to protect against Bluetooth, cordless phone, and microwave oven interference.
Receive vector diversity for multi-stream application is implemented for efficient utilization of
the MIMO channel. Efficient IQ-imbalance, DC offset, phase noise, frequency offset, and timing
offset compensations are provided for the radio frequency front-end.
The RTL8821CE supports fast receiver Automatic Gain Control (AGC) with synchronous and
asynchronous control loops among antennas, antenna diversity functions, and adaptive transmit
power control functions to obtain better performance in the analog portions of the transceiver.
The RTL8821CE MAC supports 802.11e for multimedia applications, 802.11i and WAPI
(Wireless Authentication Privacy Infrastructure) for security, and 802.11n/802.11ac for enhanced
MAC protocol efficiency. Using packet aggregation techniques such as A-MPDU with BA and
A-MSDU, protocol efficiency is significantly improved. Power saving mechanisms such as Legacy
Power Save, U-APSD, and MIMO power saving reduce the power wasted during idle time, and
compensate for the extra power required to transmit MIMO OFDM. The RTL8821CE provides
simple legacy, 20MHz/40MHz/80MHz co-existence mechanisms to ensure backward and network
compatibility.