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- In telecommunications, superframe (SF) is a T1 framing standard. In the 1970s it replaced the original T1/D1 framing scheme of the 1960s in which the framing bit simply alternated between 0 and 1. Superframe is sometimes called D4 Framing to avoid confusion with single-frequency signaling. It was first supported by the D2 channel bank, but it was first widely deployed with the D4 channel bank. In order to determine where each channel is located in the stream of data being received, each set of 24 channels is aligned in a frame. The frame is 192 bits long (8 * 24), and is terminated with a 193rd bit, the framing bit, which is used to find the end of the frame. In order for the framing bit to be located by receiving equipment, a predictable pattern is sent on this bit. Equipment will search for a bit which has the correct pattern, and will align its framing based on that bit. The pattern sent is 12 bits long, so every group of 12 frames is called a superframe. The pattern used in the 193rd bit is 100011 011100. Each channel sends two bits of call supervision data during each superframe using robbed-bit signaling during frames 6 and 12 of the superframe. More specifically, after the 6th and 12th bit in the superframe pattern, the least significant data bit of each channel (bit 8; T1 data is sent big-endian and uses 1-origin numbering) is replaced by a "channel-associated signalling" bit (bits A and B, respectively). Superframe remained in service in many places through the turn of the century, replaced by the improved extended superframe (ESF) of the 1980s in applications where its additional features were desired. (en)
- 超碼框(Superframe)是在電信領域中T1信號的一種舊式碼框模式，也稱作D4或D3/D4碼框。在1970年代取代原本1960年代的T1/D1碼框架構，取代的方式是把原本T1/D1的同步碼框替換掉。而超碼框在1980年代又被具有更多功能的延伸超碼框(Extended Super Frame)取代。 在T1信號中，將24個頻道定義為一個碼框。碼框中總共有192個位元(8 x 24)的資訊，再加上第193個位元代表碼框的結尾。 訊號接收設備為了將碼框定位，會利用結尾位元模式來定位。接收設備會搜尋正確的結尾位元模式並依照此模式來定位各個頻道。這個模式長度共有12位元，因此每12組碼框被稱為超碼框。這個結尾位元模式是1000 1101 1100。 (zh)
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- 超碼框(Superframe)是在電信領域中T1信號的一種舊式碼框模式，也稱作D4或D3/D4碼框。在1970年代取代原本1960年代的T1/D1碼框架構，取代的方式是把原本T1/D1的同步碼框替換掉。而超碼框在1980年代又被具有更多功能的延伸超碼框(Extended Super Frame)取代。 在T1信號中，將24個頻道定義為一個碼框。碼框中總共有192個位元(8 x 24)的資訊，再加上第193個位元代表碼框的結尾。 訊號接收設備為了將碼框定位，會利用結尾位元模式來定位。接收設備會搜尋正確的結尾位元模式並依照此模式來定位各個頻道。這個模式長度共有12位元，因此每12組碼框被稱為超碼框。這個結尾位元模式是1000 1101 1100。 (zh)
- In telecommunications, superframe (SF) is a T1 framing standard. In the 1970s it replaced the original T1/D1 framing scheme of the 1960s in which the framing bit simply alternated between 0 and 1. Superframe is sometimes called D4 Framing to avoid confusion with single-frequency signaling. It was first supported by the D2 channel bank, but it was first widely deployed with the D4 channel bank. Each channel sends two bits of call supervision data during each superframe using robbed-bit signaling during frames 6 and 12 of the superframe. (en)
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