HighlandPark is a codename for noise cancellation technology used in iPhone 4, iOS 5 and later. It is possibly developed in cooperation with Audience Inc.
syslog excerpts
*** ** **:**:** localhost kernel[0]: HighlandParkAudioDevice::start: 0x813cd000, highland-park mIICNub: 0x8117ae80, mIISNub: 0x81af6900, mSerialNub: 0x81b0a000, sampleRate = 44100, ol=8, oi=7
Versions
iPhone 4 (iPhone3,1 and iPhone3,2)
The version found inside this device is BOSKO_52.01.41/05559
iPhone 4 (iPhone3,3)
The version found inside this device is BOSKO_52.01.41/04143
iPhone 4S
The version found inside this device is Ams_H4P_Cdma_nb_0008/BOSKO_55.00.15/MH70.2.3.11_B7476_Ams_NB_Zorro