Characteristics of PUCCH formats

format0 There is no need for modulation and demodulation , Detect by cyclic shift , Faster , And it's a short symbol , Different ue It is distinguished by different cyclic shifts . fit URLLC,format0,1 and 2 Symbols do not increase the number of multiplexing users , When transmitting two symbols , The data transmitted by the two symbols is the same , It's just a promotion ack Reliability of feedback .
format1 Modulation and demodulation are required , And user reuse is very powerful , fit EMBB, Long symbol , Improve uplink coverage .
format2 Short symbol , User reuse is not supported , Can pass a lot of bit, It's all about URLCC The design of the ,format2
format3 Long symbol , User reuse is not supported , Can pass a lot of bit, yes format1 Form complementarities , fit EMBB
format4 Long symbol , Take into account the characteristics of transmission length and user multiplexing , But why? format4 Can only be 2 A or 4 Users reuse , According to the number of orthogonal sequences , For example 2 Orthogonal sequences , stay 12 When subcarriers , yes 6 Data is placed twice : For example, the first subcarrier of the first user is a1, The first 6 Subcarriers are also placed a1. Then the first subcarrier of the second user is b1, The first 6 Subcarriers are placed b（-1）. At this time, what is placed on the first subcarrier is a+b, And the first 6 Subcarrier placement is a-b, The data on these two subcarriers can be parsed a and b.
sr Sending alone can only be used format0 and 1
When sr and ack, perhaps csi When reusing , Once order ue exceed 2 individual bit Will use format2~4, And the order is ACK+SR+CSI