Research&DSP Implementation Of Technologies In LTE Physical Uplink Control Channel

Since the conception of honeycomb cell was proposed in1970s, the mobile communication developed rapidly. The3G mobile communication systems achieved the high-speed data transmission and multimedia business in just a few decades. Due to the limitations of the3G technology and increasing communication demands among people, there is a higher demand on the mobile communication system. So the3GPP (3rd Generation Partnership Project) start the LTE project to achieve high-speed data transmission, which downlink peak rate is up to100Mbits/s, and uplink50Mbits/s. The bandwidth of LTE is flexible:20M,15M,10M,5M,3M,1.4M;LTE uplink channels include PUSCH, PUCCH and PRACH. The controlling information is transmitted in control channel, which is independent of any upstream data packet. The mainly function of PUCCH is reflected in controlling date transmission. If UE want to communicate with others, firstly a scheduling request must be transmitted to get resource allocation, then the data could be sent. According to the current channel quality, the resource allocation of UE (with different priority) is different. And whether the UE data was transmitted successfully, whether it is need to retransmit HARQ, all of this is controlled by PUCCH. So PUCCH plays a key role in LTE.This paper focused on the key technology of PUCCH and building the physical link for simulating, then implementing the function of control channel on MSC8156chip. It introduced the PUCCH channel transmitter and the receiver process. JOB scheduling mechanism in designing the DSP system architecture on the MSC8156chip was also mentioned. Making detailed introduction of the DSP, L1interface and other high-level interface, including the FPGA interrupt interface of the L1, MAC scheduling message interface of the L2, RRC district-level interface of the L3. Uplink system was a combination of static scheduling action on the MSC8156. The PUSCH is dynamically allocated among corel-core3, the PUCCH is statically allocated on core4and the PRACH is statically assigned on core5. And finally, the functional and performance tests were carried out in Single-core DSP through multiple test cases in unit test. Analysis of experimental results shown that the design can achieve the functional and timing requirement. This kind of design has been applied in developing of LTE system.