Comments 10
DRM наверное был бы эффективен для локального вещания на КВ, когда антена излучает в зенит. Дальних скачков мы не получим, зато будем иметь покрытие радиусом 200-300-400км по сути без мертвых зон. Без замирания и прочих прелестей характерных для дальнего распространения сигнала
Да, как можно видеть из таблицы выше, поддержка NVIS в стандарте есть. Но битрейт 12-20КБит/с для нормального звука все равно мало.
DRM broadcasting can be done using a choice of different bandwidths:
4.5 kHz. Gives the ability for the broadcaster to do a simulcast and use the lower-sideband area of a 9 kHz raster channel for AM, with a 4.5 kHz DRM signal occupying the area traditionally taken by the upper-sideband.However the resulting bit rate and audio quality is not good.
5 kHz. Gives the ability for the broadcaster to do a simulcast and use the lower-sideband area of a 10 kHz raster channel for AM, with a 5 kHz DRM signal occupying the area traditionally taken by the upper-sideband. However the resulting bit rate and audio quality is marginal (7.1–16.7 kbit/s for 5 kHz). This technique could be used on the shortwave bands throughout the world.
9 kHz. Occupies half the standard bandwidth of a region 1 long wave or medium wave broadcast channel.
10 kHz. Occupies half the standard bandwidth of a region 2 broadcast channel. could be used to simulcast with analogue audio channel restricted to NRSC5. Occupies a full worldwide short wave broadcast channel (giving 14.8–34.8 kbit/s)
18 kHz. Occupies full bandwidth of region 1 long wave or medium wave channels according to the existing frequency plan. This offers better audio quality.
20 kHz. Occupies full bandwidth of region 2 or region 3 AM channel according to the existing frequency plan. This offers highest audio quality of the DRM30 standard (giving 30.6–72 kbit/s).
100 kHz for DRM+. This bandwidth can be used in band I, II, and III and DRM+ can transmit four different programs in this bandwidth or even one low definition digital video channel.
4.5 kHz. Gives the ability for the broadcaster to do a simulcast and use the lower-sideband area of a 9 kHz raster channel for AM, with a 4.5 kHz DRM signal occupying the area traditionally taken by the upper-sideband.However the resulting bit rate and audio quality is not good.
5 kHz. Gives the ability for the broadcaster to do a simulcast and use the lower-sideband area of a 10 kHz raster channel for AM, with a 5 kHz DRM signal occupying the area traditionally taken by the upper-sideband. However the resulting bit rate and audio quality is marginal (7.1–16.7 kbit/s for 5 kHz). This technique could be used on the shortwave bands throughout the world.
9 kHz. Occupies half the standard bandwidth of a region 1 long wave or medium wave broadcast channel.
10 kHz. Occupies half the standard bandwidth of a region 2 broadcast channel. could be used to simulcast with analogue audio channel restricted to NRSC5. Occupies a full worldwide short wave broadcast channel (giving 14.8–34.8 kbit/s)
18 kHz. Occupies full bandwidth of region 1 long wave or medium wave channels according to the existing frequency plan. This offers better audio quality.
20 kHz. Occupies full bandwidth of region 2 or region 3 AM channel according to the existing frequency plan. This offers highest audio quality of the DRM30 standard (giving 30.6–72 kbit/s).
100 kHz for DRM+. This bandwidth can be used in band I, II, and III and DRM+ can transmit four different programs in this bandwidth or even one low definition digital video channel.
Увы, USRP на КВ не передает
Разве? А как же карты UBX, BasicTX, LFTX?
На Амазоне он со статусом Currently unavailable давным-давно висит.
Со вторым кстати интересно, это тот же Gospell GR-216, который описан в тексте, но продаваемый под маркой Tecsun Q-3061 на австралийский рынок.
The Tecsun Radios Australia Q-3061 DRM Shortwave Radio has been a long time coming and after evaluating dozens of samples over the years we have finally found a stand-alone desktop DRM radio that is suitable for Australian, New Zealand, and Pacific Islands listeners.
Может что-то там у них и передается, интересно.
The Tecsun Radios Australia Q-3061 DRM Shortwave Radio has been a long time coming and after evaluating dozens of samples over the years we have finally found a stand-alone desktop DRM radio that is suitable for Australian, New Zealand, and Pacific Islands listeners.
Может что-то там у них и передается, интересно.
www.rtl-sdr.com/big-list-rtl-sdr-supported-software огромный список ПО для SDR.
Сам не проверял, но в 2х программах заявлена поддержка DRM+: Wavesink Plus
и Sodira.
Спасибо за отличный цикл статей.
Сам не проверял, но в 2х программах заявлена поддержка DRM+: Wavesink Plus
и Sodira.
Спасибо за отличный цикл статей.
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