diff options
| author | Tom Tsou <tom.tsou@ettus.com> | 2016-08-11 14:36:23 -0700 |
|---|---|---|
| committer | Tom Tsou <tom.tsou@ettus.com> | 2016-08-11 14:44:57 -0700 |
| commit | aa15d62a8cac2bfa30a336b76cd18f3b9647dd0d (patch) | |
| tree | 734a1f76f6d01306df20ed681e3515469896cc1f | |
| parent | 2e5e2c537bfca9bebddcc40391227a2074bc3b88 (diff) | |
sigproc: Match differential GMSK start/end bits to tail bits
Invert the initial and trailing diffential bits in the 4 sps
GMSK modulator to fix power-time mask irregularity at start
and end of burst. GSM tail bits are always zero, so we can
safely use fixed bit values.
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
| -rw-r--r-- | Transceiver52M/sigProcLib.cpp | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/Transceiver52M/sigProcLib.cpp b/Transceiver52M/sigProcLib.cpp index d274e26..a361eff 100644 --- a/Transceiver52M/sigProcLib.cpp +++ b/Transceiver52M/sigProcLib.cpp @@ -816,8 +816,8 @@ static signalVector *modulateBurstLaurent(const BitVector &bits) c1_burst->isReal(true); c1_itr = c1_burst->begin(); - /* Padded differential start bits */ - *c0_itr = 2.0 * (0x01 & 0x01) - 1.0; + /* Padded differential tail bits */ + *c0_itr = 2.0 * (0x00 & 0x01) - 1.0; c0_itr += sps; /* Main burst bits */ @@ -826,8 +826,8 @@ static signalVector *modulateBurstLaurent(const BitVector &bits) c0_itr += sps; } - /* Padded differential end bits */ - *c0_itr = 2.0 * (0x01 & 0x01) - 1.0; + /* Padded differential tail bits */ + *c0_itr = 2.0 * (0x00 & 0x01) - 1.0; /* Generate C0 phase coefficients */ GMSKRotate(*c0_burst, sps); |