From 8bb7afbdc7cab7010c5bfb5a0b750a62d953aedf Mon Sep 17 00:00:00 2001 From: "Matthias P. Braendli" Date: Thu, 4 May 2023 13:27:10 +0200 Subject: Revert "Normalise TII to 1/sqrt(48)" and fix TII level in GainControl This reverts commit c7961c2e8688d6db2a87b5079c60a04b8fe37e74. --- src/TII.cpp | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'src/TII.cpp') diff --git a/src/TII.cpp b/src/TII.cpp index 2d7429f..b329cdb 100644 --- a/src/TII.cpp +++ b/src/TII.cpp @@ -189,8 +189,6 @@ int TII::process(Buffer* dataIn, Buffer* dataOut) complexf* in = reinterpret_cast(dataIn->getData()); complexf* out = reinterpret_cast(dataOut->getData()); - constexpr float normalisation = 0.144337f; // 1/sqrt(48); - /* Normalise the TII carrier power according to ETSI TR 101 496-3 * Clause 5.4.2.2 Paragraph 7: * @@ -198,7 +196,8 @@ int TII::process(Buffer* dataIn, Buffer* dataOut) * > is 1:48 for all Modes, so that the signal power in a TII symbol is * > 16 dB below the signal power of the other symbols. * - * Divide by sqrt(48) because I and Q are separately normalised. + * This is because we only enable 32 out of 1536 carriers, not because + * every carrier is lower power. */ for (size_t i = 0; i < m_Acp.size(); i++) { /* See header file for an explanation of the old variant. @@ -219,8 +218,8 @@ int TII::process(Buffer* dataIn, Buffer* dataOut) * and fuse the two conditionals together: */ if (m_Acp[i]) { - out[i] = in[i] * normalisation; - out[i+1] = (m_conf.old_variant ? in[i+1] : in[i]) * normalisation; + out[i] = in[i]; + out[i+1] = (m_conf.old_variant ? in[i+1] : in[i]); } } } -- cgit v1.2.3