Codebook design method for multiple input multiple output system and method for using the codebook
View Patent ↗A multiple input multiple output (MIMO) communication method using a codebook is provided. The MIMO communication method may use one or more codebooks and the codebooks may change according to a transmission rank, a channel state of a user terminal, and/or a number of feedback bits.
1. A terminal in a multiple input multiple output (MIMO) communication system, the terminal comprising:
a memory configured to store a 6-bit codebook comprising 64 codeword matrices;
a channel estimator configured to estimate a channel formed between a base station and the terminal;
a processor configured to select a preferred codeword vector from the codebook stored in the memory; and
a feedback unit configured to feed back feedback data associated with the preferred codeword vector to the base station, wherein the 6-bit codebook comprises columns 1 through 64:
columns 1 through 4
0.5000
0.3260 + 0.6774i
0.1499 + 0.0347i
0.5000
0.3254 + 0.1709i
0.5009 + 0.3071i
0.5000
0.3254 + 0.1709i
0.1505 + 0.5412i
0.5000
−0.0250 + 0.4051i
0.1505 + 0.5412i
0.5000
0.0918 + 0.3270i
0.5000
0.1311 + 0.6387i
0.5000
0.2473 + 0.0541i
0.5000
0.4815 + 0.4045i
columns 5 through 8
0.5000
0.0918 + 0.3270i
0.3841 + 0.3851i
−0.5000
−0.1311 − 0.6387i
0.0056 − 0.3076i
0.5000
0.2473 + 0.0541i
0.2285 + 0.6580i
−0.5000
−0.4815 − 0.4045i
−0.3448 − 0.0735i
0.5000
0.3260 + 0.6774i
−0.5000
−0.3254 − 0.1709i
0.5000
0.3254 + 0.1709i
−0.5000
0.0250 − 0.4051i
columns 9 through 12
−0.5000
−0.0918 − 0.3270i
−0.0337 − 0.6193i
−0.5000
−0.2473 − 0.0541i
−0.4621 − 0.5019i
0.5000
0.1311 + 0.6387i
0.2280 + 0.1515i
0.5000
0.4815 + 0.4045i
0.2280 + 0.1515i
−0.5000
−0.4422 − 0.0928i
−0.5000
−0.2479 − 0.5606i
0.5000
0.2479 + 0.5606i
0.5000
0.0137 + 0.2102i
columns 13 through 16
−0.5000
−0.4422 − 0.0928i
−0.3841 − 0.3851i
0.5000
0.2479 + 0.5606i
−0.0056 + 0.3076i
0.5000
0.2479 + 0.5606i
0.3448 + 0.0735i
−0.5000
−0.0137 − 0.2102i
−0.2285 − 0.6580i
−0.5000
−0.0918 − 0.3270i
0.5000
0.2473 + 0.0541i
0.5000
0.1311 + 0.6387i
−0.5000
−0.4815 − 0.4045i
columns 17 through 20
0.5000
0.3841 + 0.3851i
0.0918 + 0.3270i
0 + 0.5000i
−0.3076 − 0.0056i
−0.0541 + 0.2473i
0.5000
0.3448 + 0.0735i
0.1311 + 0.6387i
0 + 0.5000i
−0.6580 + 0.2285i
−0.4045 + 0.4815i
0.5000
0.0337 + 0.6193i
0 + 0.5000i
−0.5019 + 0.4621i
0.5000
0.2280 + 0.1515i
0 + 0.5000i
−0.1515 + 0.2280i
columns 21 through 24
0.5000
0.0337 + 0.6193i
0.4422 + 0.0928i
0 − 0.5000i
0.5019 − 0.4621i
0.5606 − 0.2479i
0.5000
0.2280 + 0.1515i
0.2479 + 0.5606i
0 − 0.5000i
0.1515 − 0.2280i
0.2102 − 0.0137i
0.5000
0.3841 + 0.3851i
0 − 0.5000i
0.3076 + 0.0056i
0.5000
0.3448 + 0.0735i
0 − 0.5000i
0.6580 − 0.2285i
columns 25 through 28
−0.5000
−0.3841 − 0.3851i
−0.3260 − 0.6774i
0 − 0.5000i
0.3076 + 0.0056i
0.1709 − 0.3254i
0.5000
0.2285 + 0.6580i
0.3254 + 0.1709i
0 + 0.5000i
−0.0735 + 0.3448i
−0.4051 − 0.0250i
−0.5000
−0.1499 − 0.0347i
0 − 0.5000i
0.3071 − 0.5009i
0.5000
0.1505 + 0.5412i
0 + 0.5000i
−0.5412 + 0.1505i
columns 29 through 32
−0.5000
−0.1499 − 0.0347i
−0.0918 − 0.3270i
0 + 0.5000i
−0.3071 + 0.5009i
−0.6387 + 0.1311i
0.5000
0.1505 + 0.5412i
0.2473 + 0.0541i
0 − 0.5000i
0.5412 − 0.1505i
0.4045 − 0.4815i
−0.5000
−0.3841 − 0.3851i
0 + 0.5000i
−0.3076 − 0.0056i
0.5000
0.2285 + 0.6580i
0 − 0.5000i
0.0735 − 0.3448i
columns 33 through 36
0.5000
0.0337 + 0.6193i
0.0918 + 0.3270i
0.5000
0.2280 + 0.1515i
0.4815 + 0.4045i
0.5000
0.2280 + 0.1515i
0.1311 + 0.6387i
−0.5000
−0.4621 − 0.5019i
−0.2473 − 0.0541i
0.5000
0.3841 + 0.3851i
0.5000
0.2285 + 0.6580i
0.5000
0.3448 + 0.0735i
−0.5000
0.0056 − 0.3076i
columns 37 through 40
0.5000
0.4422 + 0.0928i
0.0337 + 0.6193i
0 + 0.5000i
−0.2102 + 0.0137i
−0.1515 + 0.2280i
−0.5000
−0.2479 − 0.5606i
−0.2280 − 0.1515i
0 + 0.5000i
−0.5606 + 0.2479i
−0.5019 + 0.4621i
0.5000
0.0918 + 0.3270i
0 + 0.5000i
−0.4045 + 0.4815i
−0.5000
−0.1311 − 0.6387i
0 + 0.5000i
−0.0541 + 0.2473i
columns 41 through 44
0.5000
0.3841 + 0.3851i
0.4422 + 0.0928i
−0.5000
−0.2285 − 0.6580i
−0.0137 − 0.2102i
0.5000
0.3448 + 0.0735i
0.2479 + 0.5606i
0.5000
−0.0056 + 0.3076i
0.2479 + 0.5606i
0.5000
0.0337 + 0.6193i
−0.5000
−0.2280 − 0.1515i
0.5000
0.2280 + 0.1515i
0.5000
0.4621 + 0.5019i
columns 45 through 48
0.5000
0.0918 + 0.3270i
0.3841 + 0.3851i
0 − 0.5000i
0.4045 − 0.4815i
0.6580 − 0.2285i
−0.5000
−0.1311 − 0.6387i
−0.3448 − 0.0735i
0 − 0.5000i
0.0541 − 0.2473i
0.3076 + 0.0056i
0.5000
0.4422 + 0.0928i
0 − 0.5000i
0.2102 − 0.0137i
−0.5000
−0.2479 − 0.5606i
0 − 0.5000i
0.5606 − 0.2479i
columns 49 through 52
0.5000
0.3841 + 0.3851i
−0.1560 + 0.4926i
0.3536 + 0.3536i
0.0022 + 0.1690i
0.0837 + 0.4175i
0 + 0.5000i
−0.3076 − 0.0056i
−0.4597 + 0.3989i
−0.3536 + 0.3536i
−0.7536 − 0.1140i
−0.4175 + 0.0837i
0.5000
0.3841 + 0.3851i
0.3536 + 0.3536i
−0.1140 + 0.7536i
0 + 0.5000i
−0.3076 − 0.0056i
−0.3536 + 0.3536i
−0.1690 + 0.0022i
columns 53 through 56
0.5000
0.3396 + 0.1614i
0.3841 + 0.3851i
−0.3536 + 0.3536i
−0.3400 − 0.3060i
−0.1690 + 0.0022i
0 − 0.5000i
0.3493 − 0.5641i
0.3076 + 0.0056i
0.3536 + 0.3536i
−0.3060 + 0.3400i
−0.1140 + 0.7536i
0.5000
−0.1560 + 0.4926i
−0.3536 + 0.3536i
−0.4175 + 0.0837i
0 − 0.5000i
0.4597 − 0.3989i
0.3536 + 0.3536i
0.0837 + 0.4175i
columns 57 through 60
0.5000
0.3841 + 0.3851i
0.3396 + 0.1614i
−0.3536 − 0.3536i
0.1140 − 0.7536i
0.3060 − 0.3400i
0 + 0.5000i
−0.3076 − 0.0056i
−0.3493 + 0.5641i
0.3536 − 0.3536i
0.1690 − 0.0022i
0.3400 + 0.3060i
0.5000
0.3841 + 0.3851i
−0.3536 − 0.3536i
−0.0022 − 0.1690i
0 + 0.5000i
−0.3076 − 0.0056i
0.3536 − 0.3536i
0.7536 + 0.1140i
columns 61 through 64
0.5000
−0.1560 + 0.4926i
0.3841 + 0.3851i
0.3536 − 0.3536i
0.4175 − 0.0837i
0.7536 + 0.1140i
0 − 0.5000i
0.4597 − 0.3989i
0.3076 + 0.0056i
−0.3536 − 0.3536i
−0.0837 − 0.4175i
−0.0022 − 0.1690i
0.5000
0.3396 + 0.1614i
0.3536 − 0.3536i
0.3400 + 0.3060i
0 − 0.5000i
0.3493 − 0.5641i
−0.3536 − 0.3536i
0.3060 − 0.3400i.
2. A terminal in a multiple input multiple output (MIMO) communication system, the terminal comprising:
a memory configured to store a 6-bit codebook comprising 64 codeword matrices;
a channel estimator configured to estimate a channel formed between a base station and the terminal;
a processor configured to select a preferred codeword vector from the codebook stored in the memory; and
a feedback unit configured to feed back feedback data associated with the preferred codeword vector to the base station, wherein the 6-bit codebook comprises columns 1 through 64:
columns 1 through 4
0.5000
0.3049 + 0.6229i
0.1779 + 0.0995i
0.0191 + 0.3371i
0.5000
0.2626 + 0.1626i
0.5060 + 0.2740i
0.1673 + 0.6390i
0.5000
0.4213 + 0.2108i
0.0614 + 0.5116i
0.3261 + 0.1156i
0.5000
−0.0232 + 0.4484i
0.2202 + 0.5598i
0.4531 + 0.3532i
columns 5 through 8
0.5000
0.0191 + 0.3371i
0.4637 + 0.3853i
0.3049 + 0.6229i
−0.5000
−0.1673 − 0.6390i
−0.0297 − 0.3692i
−0.2626 − 0.1626i
0.5000
0.3261 + 0.1156i
0.1567 + 0.6069i
0.4213 + 0.2108i
−0.5000
−0.4531 − 0.3532i
−0.3155 − 0.0834i
0.0232 − 0.4484i
columns 9 through 12
−0.5000
−0.1779 − 0.3853i
−0.0191 − 0.6229i
−0.4637 − 0.0995i
−0.5000
−0.2202 − 0.0834i
−0.4531 − 0.4484i
−0.3155 − 0.5598i
0.5000
0.0614 + 0.6069i
0.3261 + 0.2108i
0.1567 + 0.5116i
0.5000
0.5060 + 0.3692i
0.1673 + 0.1626i
0.0297 + 0.2740i
columns 13 through 16
−0.5000
−0.4637 − 0.0995i
−0.3049 − 0.3371i
−0.1779 − 0.3853i
0.5000
0.3155 + 0.5598i
−0.0232 + 0.3532i
0.2202 + 0.0834i
0.5000
0.1567 + 0.5116i
0.4213 + 0.1156i
0.0614 + 0.6069i
−0.5000
−0.0297 − 0.2740i
−0.2626 − 0.6390i
−0.5060 − 0.3692i
columns 17 through 20
0.5000
0.3049 + 0.3371i
0.1779 + 0.3853i
0.0191 + 0.6229i
0 + 0.5000i
−0.3532 − 0.0232i
−0.0834 + 0.2202i
−0.4484 + 0.4531i
0.5000
0.4213 + 0.1156i
0.0614 + 0.6069i
0.3261 + 0.2108i
0 + 0.5000i
−0.6390 + 0.2626i
−0.3692 + 0.5060i
−0.1626 + 0.1673i
columns 21 through 24
0.5000
0.0191 + 0.6229i
0.4637 + 0.0995i
0.3049 + 0.3371i
0 − 0.5000i
0.4484 − 0.4531i
0.5598 − 0.3155i
0.3532 + 0.0232i
0.5000
0.3261 + 0.2108i
0.1567 + 0.5116i
0.4213 + 0.1156i
0 − 0.5000i
0.1626 − 0.1673i
0.2740 − 0.0297i
0.6390 − 0.2626i
columns 25 through 28
−0.5000
−0.4637 − 0.3853i
−0.3049 − 0.6229i
−0.1779 − 0.0995i
0 − 0.5000i
0.3692 − 0.0297i
0.1626 − 0.2626i
0.2740 − 0.5060i
0.5000
0.1567 + 0.6069i
0.4213 + 0.2108i
0.0614 + 0.5116i
0 + 0.5000i
−0.0834 + 0.3155i
−0.4484 − 0.0232i
−0.5598 + 0.2202i
columns 29 through 32
−0.5000
−0.1779 − 0.0995i
−0.0191 − 0.3371i
−0.4637 − 0.3853i
0 + 0.5000i
−0.2740 + 0.5060i
−0.6390 + 0.1673i
−0.3692 + 0.0297i
0.5000
0.0614 + 0.5116i
0.3261 + 0.1156i
0.1567 + 0.6069i
0 − 0.5000i
0.5598 − 0.2202i
0.3532 − 0.4531i
0.0834 − 0.3155i
columns 33 through 36
0.5000
0.0191 + 0.6229i
0.1779 + 0.3853i
0.3049 + 0.3371i
0.5000
0.1673 + 0.1626i
0.5060 + 0.3692i
0.2626 + 0.6390i
0.5000
0.3261 + 0.2108i
0.0614 + 0.6069i
0.4213 + 0.1156i
−0.5000
−0.4531 − 0.4484i
−0.2202 − 0.0834i
0.0232 − 0.3532i
columns 37 through 40
0.5000
0.4637 + 0.0995i
0.0191 + 0.6229i
0.1779 + 0.3853i
0 + 0.5000i
−0.2740 + 0.0297i
−0.1626 + 0.1673i
−0.3692 + 0.5060i
−0.5000
−0.1567 − 0.5116i
−0.3261 − 0.2108i
−0.0614 − 0.6069i
0 + 0.5000i
−0.5598 + 0.3155i
−0.4484 + 0.4531i
−0.0834 + 0.2202i
columns 41 through 44
0.5000
0.3049 + 0.3371i
0.4637 + 0.0995i
0.0191 + 0.6229i
−0.5000
−0.2626 − 0.6390i
−0.0297 − 0.2740i
−0.1673 − 0.1626i
0.5000
0.4213 + 0.1156i
0.1567 + 0.5116i
0.3261 + 0.2108i
0.5000
−0.0232 + 0.3532i
0.3155 + 0.5598i
0.4531 + 0.4484i
columns 45 through 48
0.5000
0.1779 + 0.3853i
0.3049 + 0.3371i
0.4637 + 0.0995i
0 − 0.5000i
0.3692 − 0.5060i
0.6390 − 0.2626i
0.2740 − 0.0297i
−0.5000
−0.0614 − 0.6069i
−0.4213 − 0.1156i
−0.1567 − 0.5116i
0 − 0.5000i
0.0834 − 0.2202i
0.3532 + 0.0232i
0.5598 − 0.3155i
columns 49 through 52
0.5000
0.3602 + 0.4406i
−0.0795 + 0.4839i
0.3602 + 0.4406i
0.3536 + 0.3536i
−0.0754 + 0.1870i
0.0965 + 0.3794i
−0.0754 + 0.7586i
0 + 0.5000i
−0.2289 + 0.0434i
−0.5609 + 0.3720i
−0.2289 + 0.0434i
−0.3536 + 0.3536i
−0.7586 − 0.0754i
−0.3794 + 0.0965i
−0.1870 − 0.0754i
columns 53 through 56
0.5000
0.3247 + 0.0797i
0.3602 + 0.4406i
−0.0795 + 0.4839i
−0.3536 + 0.3536i
−0.3794 − 0.2846i
−0.1870 − 0.0754i
−0.3794 + 0.0965i
0 − 0.5000i
0.4262 − 0.5068i
0.2289 − 0.0434i
0.5609 − 0.3720i
0.3536 + 0.3536i
−0.2846 + 0.3794i
−0.0754 + 0.7586i
0.0965 + 0.3794i
columns 57 through 60
0.5000
0.3602 + 0.4406i
0.3247 + 0.0797i
0.3602 + 0.4406i
−0.3536 − 0.3536i
0.0754 − 0.7586i
0.2846 − 0.3794i
0.0754 − 0.1870i
0 + 0.5000i
−0.2289 + 0.0434i
−0.4262 + 0.5068i
−0.2289 + 0.0434i
0.3536 − 0.3536i
0.1870 + 0.0754i
0.3794 + 0.2846i
0.7586 + 0.0754i
columns 61 through 64
0.5000
−0.0795 + 0.4839i
0.3602 + 0.4406i
0.3247 + 0.0797i
0.3536 − 0.3536i
0.3794 − 0.0965i
0.7586 + 0.0754i
0.3794 + 0.2846i
0 − 0.5000i
0.5609 − 0.3720i
0.2289 − 0.0434i
0.4262 − 0.5068i
−0.3536 − 0.3536i
−0.0965 − 0.3794i
0.0754 − 0.1870i
0.2846 − 0.3794i.
3. A base station in a multiple input multiple output (MIMO) communication system, the base station comprising:
a memory configured to store a 6-bit codebook comprising 64 codeword matrices;
a processor configured to verify a preferred codeword vector of a terminal from the codebook stored in the memory; and
a precoder configured to precode at least one data stream using a precoding matrix corresponding to the preferred codeword vector, wherein the 6-bit codebook comprises columns 1 through 64:
columns 1 through 4
0.5000
0.3260 + 0.6774i
0.1499 + 0.0347i
0.0918 + 0.3270i
0.5000
0.3254 + 0.1709i
0.5009 + 0.3071i
0.1311 + 0.6387i
0.5000
0.3254 + 0.1709i
0.1505 + 0.5412i
0.2473 + 0.0541i
0.5000
−0.0250 + 0.4051i
0.1505 + 0.5412i
0.4815 + 0.4045i
columns 5 through 8
0.5000
0.0918 + 0.3270i
0.3841 + 0.3851i
0.3260 + 0.6774i
−0.5000
−0.1311 − 0.6387i
0.0056 − 0.3076i
−0.3254 − 0.1709i
0.5000
0.2473 + 0.0541i
0.2285 + 0.6580i
0.3254 + 0.1709i
−0.5000
−0.4815 − 0.4045i
−0.3448 − 0.0735i
0.0250 − 0.4051i
columns 9 through 12
−0.5000
−0.0918 − 0.3270i
−0.0337 − 0.6193i
−0.4422 − 0.0928i
−0.5000
−0.2473 − 0.0541i
−0.4621 − 0.5019i
−0.2479 − 0.5606i
0.5000
0.1311 + 0.6387i
0.2280 + 0.1515i
0.2479 + 0.5606i
0.5000
0.4815 + 0.4045i
0.2280 + 0.1515i
0.0137 + 0.2102i
columns 13 through 16
−0.5000
−0.4422 − 0.0928i
−0.3841 − 0.3851i
−0.0918 − 0.3270i
0.5000
0.2479 + 0.5606i
−0.0056 + 0.3076i
0.2473 + 0.0541i
0.5000
0.2479 + 0.5606i
0.3448 + 0.0735i
0.1311 + 0.6387i
−0.5000
−0.0137 − 0.2102i
−0.2285 − 0.6580i
−0.4815 − 0.4045i
columns 17 through 20
0.5000
0.3841 + 0.3851i
0.0918 + 0.3270i
0.0337 + 0.6193i
0 + 0.5000i
−0.3076 − 0.0056i
−0.0541 + 0.2473i
−0.5019 + 0.4621i
0.5000
0.3448 + 0.0735i
0.1311 + 0.6387i
0.2280 + 0.1515i
0 + 0.5000i
−0.6580 + 0.2285i
−0.4045 + 0.4815i
−0.1515 + 0.2280i
columns 21 through 24
0.5000
0.0337 + 0.6193i
0.4422 + 0.0928i
0.3841 + 0.3851i
0 − 0.5000i
0.5019 − 0.4621i
0.5606 − 0.2479i
0.3076 + 0.0056i
0.5000
0.2280 + 0.1515i
0.2479 + 0.5606i
0.3448 + 0.0735i
0 − 0.5000i
0.1515 − 0.2280i
0.2102 − 0.0137i
0.6580 − 0.2285i
columns 25 through 28
−0.5000
−0.3841 − 0.3851i
− 0.3260 − 0.6774i
−0.1499 − 0.0347i
0 − 0.5000i
0.3076 + 0.0056i
0.1709 − 0.3254i
0.3071 − 0.5009i
0.5000
0.2285 + 0.6580i
0.3254 + 0.1709i
0.1505 + 0.5412i
0 + 0.5000i
−0.0735 + 0.3448i
−0.4051 − 0.0250i
−0.5412 + 0.1505i
columns 29 through 32
−0.5000
−0.1499 − 0.0347i
−0.0918 − 0.3270i
−0.3841 − 0.3851i
0 + 0.5000i
−0.3071 + 0.5009i
−0.6387 + 0.1311i
−0.3076 − 0.0056i
0.5000
0.1505 + 0.5412i
0.2473 + 0.0541i
0.2285 + 0.6580i
0 − 0.5000i
0.5412 − 0.1505i
0.4045 − 0.4815i
0.0735 − 0.3448i
columns 33 through 36
0.5000
0.0337 + 0.6193i
0.0918 + 0.3270i
0.3841 + 0.3851i
0.5000
0.2280 + 0.1515i
0.4815 + 0.4045i
0.2285 + 0.6580i
0.5000
0.2280 + 0.1515i
0.1311 + 0.6387i
0.3448 + 0.0735i
−0.5000
−0.4621 − 0.5019i
−0.2473 − 0.0541i
0.0056 − 0.3076i
columns 37 through 40
0.5000
0.4422 + 0.0928i
0.0337 + 0.6193i
0.0918 + 0.3270i
0 + 0.5000i
−0.2102 + 0.0137i
−0.1515 + 0.2280i
−0.4045 + 0.4815i
−0.5000
−0.2479 − 0.5606i
−0.2280 − 0.1515i
−0.1311 − 0.6387i
0 + 0.5000i
−0.5606 + 0.2479i
−0.5019 + 0.4621i
−0.0541 + 0.2473i
columns 41 through 44
0.5000
0.3841 + 0.3851i
0.4422 + 0.0928i
0.0337 + 0.6193i
−0.5000
−0.2285 − 0.6580i
−0.0137 − 0.2102i
−0.2280 − 0.1515i
0.5000
0.3448 + 0.0735i
0.2479 + 0.5606i
0.2280 + 0.1515i
0.5000
−0.0056 + 0.3076i
0.2479 + 0.5606i
0.4621 + 0.5019i
columns 45 through 48
0.5000
0.0918 + 0.3270i
0.3841 + 0.3851i
0.4422 + 0.0928i
0 − 0.5000i
0.4045 − 0.4815i
0.6580 − 0.2285i
0.2102 − 0.0137i
−0.5000
−0.1311 − 0.6387i
−0.3448 − 0.0735i
−0.2479 − 0.5606i
0 − 0.5000i
0.0541 − 0.2473i
0.3076 + 0.0056i
0.5606 − 0.2479i
columns 49 through 52
0.5000
0.3841 + 0.3851i
−0.1560 + 0.4926i
0.3841 + 0.3851i
0.3536 + 0.3536i
0.0022 + 0.1690i
0.0837 + 0.4175i
−0.1140 + 0.7536i
0 + 0.5000i
−0.3076 − 0.0056i
−0.4597 + 0.3989i
−0.3076 − 0.0056i
−0.3536 + 0.3536i
−0.7536 − 0.1140i
−0.4175 + 0.0837i
−0.1690 + 0.0022i
columns 53 through 56
0.5000
0.3396 + 0.1614i
0.3841 + 0.3851i
−0.1560 + 0.4926i
−0.3536 + 0.3536i
−0.3400 − 0.3060i
−0.1690 + 0.0022i
−0.4175 + 0.0837i
0 − 0.5000i
0.3493 − 0.5641i
0.3076 + 0.0056i
0.4597 − 0.3989i
0.3536 + 0.3536i
−0.3060 + 0.3400i
−0.1140 + 0.7536i
0.0837 + 0.4175i
columns 57 through 60
0.5000
0.3841 + 0.3851i
0.3396 + 0.1614i
0.3841 + 0.3851i
−0.3536 − 0.3536i
0.1140 − 0.7536i
0.3060 − 0.3400i
−0.0022 − 0.1690i
0 + 0.5000i
−0.3076 − 0.0056i
−0.3493 + 0.5641i
−0.3076 − 0.0056i
0.3536 − 0.3536i
0.1690 − 0.0022i
0.3400 + 0.3060i
0.7536 + 0.1140i
columns 61 through 64
0.5000
−0.1560 + 0.4926i
0.3841 + 0.3851i
0.3396 + 0.1614i
0.3536 − 0.3536i
0.4175 − 0.0837i
0.7536 + 0.1140i
0.3400 + 0.3060i
0 − 0.5000i
0.4597 − 0.3989i
0.3076 + 0.0056i
0.3493 − 0.5641i
−0.3536 − 0.3536i
−0.0837 − 0.4175i
−0.0022 − 0.1690i
0.3060 − 0.3400i.
4. A base station in a multiple input multiple output (MIMO) communication system, the base station comprising:
a memory configured to store a 6-bit codebook comprising 64 codeword matrices;
a processor configured to verify a preferred codeword vector of a terminal from the codebook stored in the memory; and
a precoder configured to precode at least one data stream using a precoding matrix corresponding to the preferred codeword vector, wherein the 6-bit codebook comprises columns 1 through 64:
columns 1 through 4
0.5000
0.3049 + 0.6229i
0.1779 + 0.0995i
0.0191 + 0.3371i
0.5000
0.2626 + 0.1626i
0.5060 + 0.2740i
0.1673 + 0.6390i
0.5000
0.4213 + 0.2108i
0.0614 + 0.5116i
0.3261 + 0.1156i
0.5000
−0.0232 + 0.4484i
0.2202 + 0.5598i
0.4531 + 0.3532i
columns 5 through 8
0.5000
0.0191 + 0.3371i
0.4637 + 0.3853i
0.3049 + 0.6229i
−0.5000
−0.1673 − 0.6390i
−0.0297 − 0.3692i
−0.2626 − 0.1626i
0.5000
0.3261 + 0.1156i
0.1567 + 0.6069i
0.4213 + 0.2108i
−0.5000
−0.4531 − 0.3532i
−0.3155 − 0.0834i
0.0232 − 0.4484i
columns 9 through 12
−0.5000
−0.1779 − 0.3853i
−0.0191 − 0.6229i
−0.4637 − 0.0995i
−0.5000
−0.2202 − 0.0834i
−0.4531 − 0.4484i
−0.3155 − 0.5598i
0.5000
0.0614 + 0.6069i
0.3261 + 0.2108i
0.1567 + 0.5116i
0.5000
0.5060 + 0.3692i
0.1673 + 0.1626i
0.0297 + 0.2740i
columns 13 through 16
−0.5000
−0.4637 − 0.0995i
−0.3049 − 0.3371i
−0.1779 − 0.3853i
0.5000
0.3155 + 0.5598i
−0.0232 + 0.3532i
0.2202 + 0.0834i
0.5000
0.1567 + 0.5116i
0.4213 + 0.1156i
0.0614 + 0.6069i
−0.5000
−0.0297 − 0.2740i
−0.2626 − 0.6390i
−0.5060 − 0.3692i
columns 17 through 20
0.5000
0.3049 + 0.3371i
0.1779 + 0.3853i
0.0191 + 0.6229i
0 + 0.5000i
−0.3532 − 0.0232i
−0.0834 + 0.2202i
−0.4484 + 0.4531i
0.5000
0.4213 + 0.1156i
0.0614 + 0.6069i
0.3261 + 0.2108i
0 + 0.5000i
−0.6390 + 0.2626i
−0.3692 + 0.5060i
−0.1626 + 0.1673i
columns 21 through 24
0.5000
0.0191 + 0.6229i
0.4637 + 0.0995i
0.3049 + 0.3371i
0 − 0.5000i
0.4484 − 0.4531i
0.5598 − 0.3155i
0.3532 + 0.0232i
0.5000
0.3261 + 0.2108i
0.1567 + 0.5116i
0.4213 + 0.1156i
0 − 0.5000i
0.1626 − 0.1673i
0.2740 − 0.0297i
0.6390 − 0.2626i
columns 25 through 28
−0.5000
−0.4637 − 0.3853i
−0.3049 − 0.6229i
−0.1779 − 0.0995i
0 − 0.5000i
0.3692 − 0.0297i
0.1626 − 0.2626i
0.2740 − 0.5060i
0.5000
0.1567 + 0.6069i
0.4213 + 0.2108i
0.0614 + 0.5116i
0 + 0.5000i
−0.0834 + 0.3155i
−0.4484 − 0.0232i
−0.5598 + 0.2202i
columns 29 through 32
−0.5000
−0.1779 − 0.0995i
−0.0191 − 0.3371i
−0.4637 − 0.3853i
0 + 0.5000i
−0.2740 + 0.5060i
−0.6390 + 0.1673i
−0.3692 + 0.0297i
0.5000
0.0614 + 0.5116i
0.3261 + 0.1156i
0.1567 + 0.6069i
0 − 0.5000i
0.5598 − 0.2202i
0.3532 − 0.4531i
0.0834 − 0.3155i
columns 33 through 36
0.5000
0.0191 + 0.6229i
0.1779 + 0.3853i
0.3049 + 0.3371i
0.5000
0.1673 + 0.1626i
0.5060 + 0.3692i
0.2626 + 0.6390i
0.5000
0.3261 + 0.2108i
0.0614 + 0.6069i
0.4213 + 0.1156i
−0.5000
−0.4531 − 0.4484i
−0.2202 − 0.0834i
0.0232 − 0.3532i
columns 37 through 40
0.5000
0.4637 + 0.0995i
0.0191 + 0.6229i
0.1779 + 0.3853i
0 + 0.5000i
−0.2740 + 0.0297i
−0.1626 + 0.1673i
−0.3692 + 0.5060i
−0.5000
−0.1567 − 0.5116i
−0.3261 − 0.2108i
−0.0614 − 0.6069i
0 + 0.5000i
−0.5598 + 0.3155i
−0.4484 + 0.4531i
−0.0834 + 0.2202i
columns 41 through 44
0.5000
0.3049 + 0.3371i
0.4637 + 0.0995i
0.0191 + 0.6229i
−0.5000
−0.2626 − 0.6390i
−0.0297 − 0.2740i
−0.1673 − 0.1626i
0.5000
0.4213 + 0.1156i
0.1567 + 0.5116i
0.3261 + 0.2108i
0.5000
−0.0232 + 0.3532i
0.3155 + 0.5598i
0.4531 + 0.4484i
columns 45 through 48
0.5000
0.1779 + 0.3853i
0.3049 + 0.3371i
0.4637 + 0.0995i
0 − 0.5000i
0.3692 − 0.5060i
0.6390 − 0.2626i
0.2740 − 0.0297i
−0.5000
−0.0614 − 0.6069i
−0.4213 − 0.1156i
−0.1567 − 0.5116i
0 − 0.5000i
0.0834 − 0.2202i
0.3532 + 0.0232i
0.5598 − 0.3155i
columns 49 through 52
0.5000
0.3602 + 0.4406i
−0.0795 + 0.4839i
0.3602 + 0.4406i
0.3536 + 0.3536i
−0.0754 + 0.1870i
0.0965 + 0.3794i
−0.0754 + 0.7586i
0 + 0.5000i
−0.2289 + 0.0434i
−0.5609 + 0.3720i
−0.2289 + 0.0434i
−0.3536 + 0.3536i
−0.7586 − 0.0754i
−0.3794 + 0.0965i
−0.1870 − 0.0754i
columns 53 through 56
0.5000
0.3247 + 0.0797i
0.3602 + 0.4406i
−0.0795 + 0.4839i
−0.3536 + 0.3536i
−0.3794 − 0.2846i
−0.1870 − 0.0754i
−0.3794 + 0.0965i
0 − 0.5000i
0.4262 − 0.5068i
0.2289 − 0.0434i
0.5609 − 0.3720i
0.3536 + 0.3536i
−0.2846 + 0.3794i
−0.0754 + 0.7586i
0.0965 + 0.3794i
columns 57 through 60
0.5000
0.3602 + 0.4406i
0.3247 + 0.0797i
0.3602 + 0.4406i
−0.3536 − 0.3536i
0.0754 − 0.7586i
0.2846 − 0.3794i
0.0754 − 0.1870i
0 + 0.5000i
−0.2289 + 0.0434i
−0.4262 + 0.5068i
−0.2289 + 0.0434i
0.3536 − 0.3536i
0.1870 + 0.0754i
0.3794 + 0.2846i
0.7586 + 0.0754i
columns 61 through 64
0.5000
−0.0795 + 0.4839i
0.3602 + 0.4406i
0.3247 + 0.0797i
0.3536 − 0.3536i
0.3794 − 0.0965i
0.7586 + 0.0754i
0.3794 + 0.2846i
0 − 0.5000i
0.5609 − 0.3720i
0.2289 − 0.0434i
0.4262 − 0.5068i
−0.3536 − 0.3536i
−0.0965 − 0.3794i
0.0754 − 0.1870i
0.2846 − 0.3794i.