diff options
| author | Thomas Tsou <tom@tsou.cc> | 2013-09-18 16:21:26 -0400 |
|---|---|---|
| committer | Thomas Tsou <tom@tsou.cc> | 2013-10-18 13:10:17 -0400 |
| commit | dafb33700eb7dee6ece776cd6b548721c28c9bd5 (patch) | |
| tree | c2f5918b0f65b2fd41d9a6c278e7faf23bcf6727 /Transceiver52M/sigProcLib.cpp | |
| parent | 0e44ab360ef53b0d3d28228fe1e71aa99181ded7 (diff) | |
Transceiver52M: Reduce RACH and TSC correlation windows
Start the correlation search window at 4 symbols before
the expected correlation peak. End the search at 10
symbols and 4 + maximum expected delay for RACH and TSC
bursts respectively.
This change lowers receive side cpu utilization while
maintaining reasonable timing jitter and accuracy tolerance.
Signed-off-by: Thomas Tsou <tom@tsou.cc>
Diffstat (limited to 'Transceiver52M/sigProcLib.cpp')
| -rw-r--r-- | Transceiver52M/sigProcLib.cpp | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/Transceiver52M/sigProcLib.cpp b/Transceiver52M/sigProcLib.cpp index 2350abb..7598156 100644 --- a/Transceiver52M/sigProcLib.cpp +++ b/Transceiver52M/sigProcLib.cpp @@ -1215,8 +1215,8 @@ static int detectBurst(signalVector &burst, * * Correlation window parameters: * target: Tail bits + RACH length (reduced from 41 to a multiple of 4) - * head: Search 8 symbols before target - * tail: Search 8 symbols after target + * head: Search 4 symbols before target + * tail: Search 10 symbols after target */ int detectRACHBurst(signalVector &rxBurst, float thresh, @@ -1234,8 +1234,8 @@ int detectRACHBurst(signalVector &rxBurst, return -1; target = 8 + 40; - head = 8; - tail = head; + head = 4; + tail = 10; start = (target - head) * sps - 1; len = (head + tail) * sps; @@ -1268,8 +1268,8 @@ int detectRACHBurst(signalVector &rxBurst, * * Correlation window parameters: * target: Tail + data + mid-midamble + 1/2 remaining midamblebits - * head: Search 8 symbols before target - * tail: Search 8 symbols + maximum expected delay + * head: Search 4 symbols before target + * tail: Search 4 symbols + maximum expected delay */ int analyzeTrafficBurst(signalVector &rxBurst, unsigned tsc, float thresh, int sps, complex *amp, float *toa, unsigned max_toa, @@ -1285,8 +1285,8 @@ int analyzeTrafficBurst(signalVector &rxBurst, unsigned tsc, float thresh, return -1; target = 3 + 58 + 16 + 5; - head = 8; - tail = head + max_toa; + head = 4; + tail = 4 + max_toa; start = (target - head) * sps - 1; len = (head + tail) * sps; |