ED-137 Use Cases | VOCAL Technologies

ED-137 Use Cases Here are a few typical scenarios using VOCAL's ED-137 module for both GRS and VCS. These modules need not only be used for ATM purposes; any RoIP implementation may benefit from tools that ED-137 supplies. Scenario 1: Summing audio for transmission For multiple audio streams of equal priority, the GRS sums(conferences) the audio sources and sends the combined result to radio transmitter. The ptt-id sent back in R2S matches previous assigned values so each VCS knows it’s transmitting. Scenario 2: Prioritizing audio for transmission All VCSs send their audio to GRS but only VCS-3 audio is transmitted due to its higher priority. VCS-1 and VCS-2 are locked out and this is indicated in the R2S RTP header with a ptt-id assigned to VCS-3 and the ptt-summation bit set. VCS-3 knows it is transmitting as the received ptt-id matches its previously assigned value. When VCS-3 stops sending, the scenario becomes like scenario 1 with VCS-1 & 2 audio being transmitted. A VCS can change its audio priority simply by altering the PTT mode using the send PTT API. Scenario 3 – GRS multicasts audio to VCSs The VCS sets up a multicast call with the GRS-RX/TXRX whose audio can be shared with other VCSs. The VCSs send unicast R2S while GRS sends multicast RTP. Scenario 4 – Sending SELCAL tones VCS sends SIP INFO request with SELCAL tones to be transmitted to aircraft. Scenario 5 – Sending and Receiving RTP Header extensions Sample of the sequence of APIs used for sending and receiving RTP extensions across the RTP link between the VCS and GRS. Radio over IP Solutions Radio Reference DesignsED-137 VoIP Air Traffic ManagementRoIP GatewayAnalog over IP (AoIP/RoIP) Gateway Reference DesignRadio over IP Platforms VOCAL’s optimized RoIP software is available for the following platforms. Please contact us for specific RoIP supported platforms. Processors Operating Systems Texas Instruments – C6xx (TMS320C62x, TMS320C64x, TMS320C645x, TMS320C66x, TMS320C67x), DaVinci, OMAP, C5xx (TMS320C54x, TMS320C55x) Analog Devices – Blackfin, ADSP-21xx, TigerSHARC, SHARC PowerPC, PowerQUICC MIPS – MIPS32, MIPS64, MIPS4Kc ARM – ARM7, ARM9, ARM9E, ARM10E, ARM11, StrongARM, ARMCortex-A8/A9/A15/A3x/A5x/A7x, Cortex-M3/M4/M7/M33 Intel / AMD – x86, x64 (both 32 and 64 bit modes) Linux, uClinux, BSD, Unix Microsoft Windows ACM / RTC / CE / Mobile Apple iOS / iPhone / iPad & MacOS VOCAL LANsEND Google Android Green Hills Integrity Micrium μCOS Symbian Wind River VxWorks eCOS / eCOSPro