Downlink E-RGCH/E-HICH Frame Structure 

E-RGCH and E-HICH Signature Sequences

The following table shows the signature sequence patterns. The software provides all 40 signature sequence patterns along with signature hopping as outlined in TS 25.211. The signature patterns read from left to right and are transmitted in the same order. Column two contains bit 0 of the sequence pattern and the right most column contains bit 39.

The sequence b_i,0, b_i,1, ..., b_i,39 transmitted in slot #i (shown in the figure above) is given by b_ij, = a C_ssj),m(i,40,. The orthogonal signature sequences C_{ss)m(i ,40,} are shown in the table below. Column 2 corresponds to index j=0 and the right most column corresponds to index j=39.

E-HICH and E-RGCH Signature Hopping Pattern

After you select the signature sequence pattern, the software determines the correct signature hopping pattern according to the following table. For example if you select signature sequence pattern 6, the software transmits sequence pattern 6 first, sequence pattern 12 second, sequence pattern 16 third, and then repeats this signature sequence hopping pattern until you change the signature sequence number in the Data cell. 

The index m(i) in slot #i is shown in the table below.