Complete Communications Engineering

VOCAL’s IP Intercom software is a combination of VOCAL’s VoIP and Voice Quality Enhancement solutions into one seamless package for hands-free full duplex IP communication applications.


IP intercom software block diagram

This software package can be used for any bidirectional IP based communication application, such as door bells, call boxes, and emergency call stations.


Why is Voice Quality Enhancement required?

IP intercom use diagramVoice Quality Enhancement (VQE) is required because of the acoustic coupling and background noise present in full duplex communication devices.  VQE is a collection of digital signal processing algorithms designed to overcome these acoustic challenges.  This voice enhancement software creates audio with high levels of speech intelligibility and clarity.

The VQE’s Acoustic Echo Cancellation software removes the echo that occurs between the loudspeaker and microphone of the intercom.  Without this software, the remote user would hear an echo of their voice.

Intercom devices are often deployed in public spaces where the background noise can be quite loud. Also, given the fact the user of the intercom is located a few feet from the device, the signal to noise ratio of an unprocessed microphone signal be low.  The VQE’s Noise Reduction software adaptive attenuates this background noise, while preserving the desired speech signal.  Automatic Gain Control software will dynamically boost the speech level to a comfortable listening level.

Voice Enhancement software can also include Acoustic Beamforming, Dual Mic Noise Cancellation, Parametric Equalizers, and Dynamic Range Compression.  All designed to get the optimal audio quality from the intercom device.

How is security and reliability of the solution provided?

VOCAL’s VoIP encryption uses SIP authentication, Secure SIP, SRTP, SDES, IPsec and other secure protocols.  This ensures the privacy and security of voice communications over the IP network.

From a software perspective, VOCAL’s software has been well tested on many levels.  Following coding standards, such as MISRA helps prevent any unintended vulnerabilities.  Our software has been tested to be interoperable with a large number of VoIP service providers and clients, making the communications reliable.

VOCAL also supports Multi-Level Precedence and Preemption for Intercom solutions that are used for emergency applications that need assured service.

VOCAL’s VoIP and VQE SDK is developed in-house.  The software is customizable to meet the exact requirements of your IP call box.


supported platforms

VOCAL’s optimized VoIP and VQE software is available for the following platforms. Please contact us for specific Echo Cancellation supported platforms.

ProcessorsOperating 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
  • Google Android
  • Green Hills Integrity
  • Micrium μCOS
  • Symbian
  • Wind River VxWorks
  • eCOS / eCOSPro