4 DSP
36 CONTENTS TS-590S
Figure 4-19 NR2: Active
TS-590S also incorporates an AF-type speech processor. Though it is an AF type, the speech
processor provides sufficient compression through a unique signal processing technique.
A typical voice signal tends to have the highest amplitude in the low frequency range with smaller
amplitude as the frequency range increases. That is the reason why distortion is likely to occur in the
low range while excessive compression processing is used. On the TS-590S, signal processing is
conducted to reduce the difference in amplitude between the low and high range when compression
is performed. As a result, the speech processor can raise the talk power while minimizing rasping
distorted sounds.
Besides, since the relatively emphasized high range has an effect of raising the intelligibility of the
voice, the speech processor has now become an effective feature to receive a reply in a pileup.
Figure 4-20 Speech Processor (Active/Inactive)

4.7 DSP-based Auxiliary Circuits (for TX)

4.7.1 Speech Processor (AF Processing)

Target signal