Search results
Results from the WOW.Com Content Network
DVB-Flexible Serially Concatenated Convolutional Turbo Codes with Near-Shannon bound performance for telemetry applications, CCSDS-131.2-O-1. Xiang, Xingyu; Valenti, Matthew C (2012-10-17). "Closing the Gap to the Capacity of APSK: Constellation Shaping and Degree Distributions". arXiv: 1210.4831 .
BPSK (also sometimes called PRK, phase reversal keying, or 2PSK) is the simplest form of phase shift keying (PSK). It uses two phases which are separated by 180° and so can also be termed 2-PSK. It does not particularly matter exactly where the constellation points are positioned, and in this figure they are shown on the real axis, at 0° and ...
There are several different line codes designed to be polarity insensitive [1] - whether the data stream is inverted or not, the decoded data will always be correct. The line codes with this property include differential Manchester encoding , bipolar encoding , NRZI , biphase mark code , coded mark inversion , and MLT-3 encoding .
When several separate paths from transmitter to receiver exist, a condition known as multipath, they almost never have exactly the same length so they almost never exhibit the same propagation delay.
A waterfall display depicting several PSK31 transmissions at around 14.07 MHz. The green lines indicate a station that is transmitting. PSK31 or "Phase Shift Keying, 31 Baud", also BPSK31 and QPSK31, is a popular computer-sound card-generated radioteletype mode, used primarily by amateur radio operators to conduct real-time keyboard-to-keyboard chat, most often using frequencies in the high ...
Compared with the "fast modes" (JT9E-H), FT8 is significantly more sensitive, has much narrower bandwidth, uses the vertical waterfall, and offers multi-decoding over the full displayed passband. The mode also supports two-pass decoding and use of " a priori (already known) information as it accumulates during a QSO".
An example of binary FSK. Frequency-shift keying (FSK) is a frequency modulation scheme in which digital information is encoded on a carrier signal by periodically shifting the frequency of the carrier between several discrete frequencies. [1]
Spectrogram of a PSK63 transmission on the 20-meter band, surrounded by PSK31 transmissions. PSK63 (meaning Phase Shift Keying at a rate of 63 baud) is a digital radio modulation mode used primarily in the amateur radio field to conduct real-time keyboard-to-keyboard informal text chat between amateur radio operators.