prob of detecting received message

Hi Group,

I have a data transmission which consist of 66 bits of information.
The packet is sent as long as a button is held over an RF data link.
The packet takes 50mS to send with another 50mS of dead-time between
the next repeat message.

On the receiver end, the prob of detecting the bit is 50% for either a
Zero or One. The receiver software has the ability to decode and
validate the first 64-bits at 100%. The remaining two-bits, #65 and
#66 are sent in the clear with no means to verify them.

Given the condition the the first 64 bits of information is received
correctly, what is the chance that the last two bits are correctly
decoded?

Would it be 50% each bit or is the conditional set of the first 64 bits
as 100% correct lessening the chance that the last two bits are
correct?

pdrunen

 

[night soil dalits]

<pdrunen@aol.com> wrote in message
news:1123524943.804006.122530@g49g2000cwa.googlegroups.com...

Hi Group,

I have a data transmission which consist of 66 bits of information.
The packet is sent as long as a button is held over an RF data link.
The packet takes 50mS to send with another 50mS of dead-time between
the next repeat message.

On the receiver end, the prob of detecting the bit is 50% for either a
Zero or One. The receiver software has the ability to decode and
validate the first 64-bits at 100%. The remaining two-bits, #65 and
#66 are sent in the clear with no means to verify them.

Given the condition the the first 64 bits of information is received
correctly, what is the chance that the last two bits are correctly
decoded?

Would it be 50% each bit or is the conditional set of the first 64 bits
as 100% correct lessening the chance that the last two bits are
correct?

pdrunen

you state the prob of bit detection is 50% that is assumed to be
independent. So for both bits to be true it is 25%

However, there is no means to verify them, so they must always be decoded as
true data.

You linkage of error rates on one part of the word to the other part of the
word depends upon the channel error characteristics which you have not
stated.

 

[John Larkin]

On 8 Aug 2005 11:15:43 -0700, pdrunen@aol.com wrote:

Hi Group,

I have a data transmission which consist of 66 bits of information.
The packet is sent as long as a button is held over an RF data link.
The packet takes 50mS to send with another 50mS of dead-time between
the next repeat message.

On the receiver end, the prob of detecting the bit is 50% for either a
Zero or One. The receiver software has the ability to decode and
validate the first 64-bits at 100%. The remaining two-bits, #65 and
#66 are sent in the clear with no means to verify them.

Given the condition the the first 64 bits of information is received
correctly, what is the chance that the last two bits are correctly
decoded?

If the bit error rate is 50%, that condition will never happen.

John