초록 ▼

A system and method is provided for locking a lug-type rotary closure assembly in a closed position. The locking arrangement includes a pressure warning device, which may also release internal pressure. The system cannot be unlocked and hence the closure cannot be opened, until the pressure warning

A system and method is provided for locking a lug-type rotary closure assembly in a closed position. The locking arrangement includes a pressure warning device, which may also release internal pressure. The system cannot be unlocked and hence the closure cannot be opened, until the pressure warning device has been moved to a position where it will warn of internal pressure and/or release internal pressure.

대표청구항 ▼

A system and method is provided for locking a lug-type rotary closure assembly in a closed position. The locking arrangement includes a pressure warning device, which may also release internal pressure. The system cannot be unlocked and hence the closure cannot be opened, until the pressure warning

A system and method is provided for locking a lug-type rotary closure assembly in a closed position. The locking arrangement includes a pressure warning device, which may also release internal pressure. The system cannot be unlocked and hence the closure cannot be opened, until the pressure warning device has been moved to a position where it will warn of internal pressure and/or release internal pressure. the four difference variables from the common portion of the branch metrics to provide another four of the metrics. 4. A method according to claim 3 wherein calculating the difference variables representing a difference between the common portion of the branch metrics and each of the branch metrics from the previous hypothesized state to each of the possible current states comprises: calculating a first intermediate variable as twice a product of a conjugate of a primary channel tap and a difference between a sampled signal and a summation of non-primary channel taps and hypothesized symbols corresponding to the non-primary channel taps; calculating a second intermediate variable as a product of the first intermediate variable and e-jπ/4; calculating a first one of the difference variables as a real portion of the first intermediate variable; calculating a second one of the difference variables as an imaginary portion of the first intermediate variable; calculating a third one of the difference variables as a real portion of the second intermediate variable; and calculating a fourth one of the difference variables as an imaginary portion of the second intermediate variable. 5. A method according to claim 1 further comprising: providing a total metric for the previous hypothesized state wherein the total metric for the previous hypothesized state represents an error associated with a hypothesized sequence of symbols hypothesized for the previous hypothesized state and hypothesized states preceding the previous hypothesized state; wherein combining the common portion of the branch metrics and each of the difference variables to provide a respective metric for each of the possible current states further comprises combining the total metric for the previous hypothesized state so that the metric for each of the possible current states comprises a total metric for each of the possible current states being a sum of a previous total metric for the previous hypothesized state and a respective branch metric for the respective possible current state. 6. A method according to claim 5 wherein combining the total metric for the previous hypothesized state, the common portion of the branch metrics, and each of the difference variables comprises: combining the total metric for the previous hypothesized state with the common portion of the branch metrics to provide an intermediate variable; and combining the intermediate variable with the difference variables to provide the total metric for each of the possible current states. 7. A receiver that receives communications over a communications channel, the receiver comprising: an analog-to-digital converter that generates a sampled baseband signal corresponding to a stream of transmitted symbols; and a DFSE equalizer coupled to the analog-to-digital converter to generate an estimate of the stream of transmitted symbols using a DFSE trellis including a trellis stage for each transmitted symbol, wherein the DFSE equalizer calculates metrics associated with each branch from a previous hypothesized state to each respective possible current state, wherein the DFSE equalizer calculates a common portion of branch metrics that is common to each branch metric from the previous hypothesized state to each of the possible current states, wherein the DFSE equalizer calculates difference variables representing a difference between the common portion of the branch metrics and each of the branch metrics from the previous hypothesized state to each of the possible current states, and wherein the DFSE equalizer combines the common portion of the branch metrics and each of the difference variables to provide a respective metric for each of the possible current states. 8. A receiver according to claim 7 wherein the DFSE equalizer is in a system providing 8-PSK modulation so that there are 8 possible current states fanning out from the previous hypothesized state and wherein