BASEBAND CHIP AND METHOD FOR LAYER 2 DOWNLINK DATA PROCESSING

1 . A baseband chip, comprising:

a plurality of Layer 2 circuits configured to receive Layer 1 transport blocks and generate Layer 3 data packets from the Layer 1 transport blocks in an in-line manner; and

a microcontroller unit (MCU) operatively coupled to the Layer 2 circuits and configured to control, through a plurality sets of commands, at least one of the Layer 2 circuits to generate the Layer 3 data packets from the Layer 1 transport blocks.

2 . The baseband chip of claim 1 , wherein the Layer 2 circuits comprise:

an interface configured to receive the Layer 1 transport blocks based on a set of interface commands from the MCU; and

a buffer operatively coupled to the interface and configured to store the Layer 1 transport blocks.

3 . The baseband chip of claim 2 , wherein the buffer is further configured to buffer the Layer 1 transport blocks to be adapted to Layer 1 data rate.

4 . The baseband chip of claim 2 , wherein the Layer 2 circuits further comprise:

a Media Access Control (MAC) circuit operatively coupled to the buffer and configured to process MAC headers of the Layer 1 transport blocks received from the buffer based on a set of MAC commands from the MCU; and

a Radio Link Control (RLC) circuit operatively coupled to the MAC circuit and configured to process RLC headers of the Layer 1 transport blocks received from the MAC circuit based on a set of RLC commands from the MCU.

5 . The baseband chip of claim 4 , wherein none of the MAC circuit and the RLC circuit processes payloads of the Layer 1 transport blocks stored in the buffer.

6 . The baseband chip of claim 4 , wherein the Layer 2 circuits further comprise a Packet Data Convergence Protocol (PDCP) circuit operatively coupled to the RLC circuit and the buffer and configured to, based on a set of PDCP commands from the MCU:

process PDCP headers of the Layer 1 transport blocks received from the RLC circuit;

process payloads of the Layer 1 transport blocks received from the buffer; and

generate the Layer 3 data packets based on the processed PDCP headers and payloads of the Layer 1 transport blocks.

7 . The baseband chip of claim 6 , wherein the Layer 2 circuits further comprise a Service Data Adaptation Protocol (SDAP) circuit configured to cause the PDCP circuit to organize the Layer 3 data packets based on Quality of Service (QoS).

8 . The baseband chip of claim 7 , wherein each of the SDAP, PDCP, RLC, and MAC circuits is an application-specific integrated circuit (ASIC).

9 . The baseband chip of claim 1 , further comprising a memory operatively coupled to the MCU and the Layer 2 circuits and configured to store the plurality sets of commands into a plurality of command queues to be fetched by the at least one of the Layer 2 circuits, respectively.

10 . The baseband chip of claim 9 , wherein the memory is further configured to receive a plurality sets of result statuses from the at least one of the Layer 2 circuits, and store the plurality sets of result statuses into a plurality of status queues, respectively.

11 . The baseband chip of claim 10 , wherein the MCU is further configured to:

retrieve the plurality sets of result statuses from the memory; and

generate each set of the commands for controlling a respective one of the Layer 2 circuits based on a corresponding set of the result statuses, wherein the corresponding set of the result status are from another one of the Layer 2 circuits at a lower layer in Layer 2 protocol stack than the respective one of the Layer 2 circuits.

12 . The baseband chip of claim 1 , wherein the Layer 2 circuits are configured to pass the Layer 1 transport blocks through the Layer 2 circuits without storing the Layer 1 transport blocks in an external memory.

13 . A baseband chip, comprising:

a buffer configured to store Layer 1 transport blocks;

a Medium Access Control (MAC) circuit configured to process MAC headers of the Layer 1 transport blocks received from the buffer;

a Radio Link Control (RLC) circuit configured to process RLC headers of the Layer 1 transport blocks received from the MAC circuit; and

a Packet Data Convergence Protocol (PDCP) circuit configured to:

process PDCP headers of the Layer 1 transport blocks received from the RLC circuit;

process payloads of the Layer 1 transport blocks received from the buffer; and

generate Layer 3 data packets based on the processed PDCP headers and payloads of the Layer 1 transport blocks.

14 . The baseband chip of claim 13 , wherein each of the PDCP, RLC, and MAC circuits is an application-specific integrated circuit (ASIC).

15 . The baseband chip of claim 13 , further comprising an interface configured to:

receive the Layer 1 transport blocks, and forward the Layer 1 transport blocks to the buffer; and

based on information related to the Layer 1 transport blocks and an interface lookup table (LUT) circuit, generate a set of MAC commands,

wherein the MAC circuit is configured to process the MAC headers based on the set of MAC commands.

16 . The baseband chip of claim 13 , wherein:

the MAC circuit is further configured to, based on the processed MAC headers and a MAC LUT circuit, generate a set of RLC commands; and

the RLC circuit is configured to process the RLC headers based on the set of RLC commands.

17 . The baseband chip of claim 13 , wherein:

the RLC circuit is further configured to, based on the processed RLC headers and a PDCP LUT circuit, generate a set of PDCP commands; and

the PDCP circuit is configured to, based on the set of PDCP commands, process the PDCP headers and the payloads and generate the Layer 3 data packets.

18 . The baseband chip of claim 13 , further comprising a Service Data Adaptation Protocol (SDAP) circuit configured to cause the PDCP circuit to organize the Layer 3 data packets based on Quality of Service (QoS).

19 . A method for Layer 2 downlink data processing, comprising:

receiving, by a microcontroller unit (MCU), a first set of result statuses based on information related to Layer 1 transport blocks;

providing, by the MCU, a first set of commands based on the first set of result statuses to control a Medium Access Control (MAC) circuit to process MAC headers of the Layer 1 transport blocks;

receiving, by the MCU, a second set of result statuses based on the processing result of the MAC circuit;

providing, by the MCU, a second set of commands based on the second set of result statuses to control a Radio Link Control (RLC) circuit to process RLC headers of the Layer 1 transport blocks;

receiving, by the MCU, a third set of result statuses based on the processing result of the RLC circuit; and

providing, by the MCU, a third set of commands based on the third set of result statuses to control a Packet Data Convergence Protocol (PDCP) circuit to process PDCP headers and payloads of the Layer 1 transport blocks, and generate Layer 3 data packets based on the processed PDCP headers and payloads of the Layer 1 transport blocks.

20 . The method of claim 19 , wherein:

providing each set of the commands comprises storing the respective set of the commands into a corresponding command queue in a memory; and

receiving each set of the result statuses comprises retrieving the respective set of the result statuses from a corresponding status queue in the memory.